safety belt light
04-18-2017, 11:55 AM
#1
Heel & Toe
Thread Starter
safety belt light
1990 coupe. safety belt reminder light on dash stays on all the time, annoying as hell. have had no luck in extinguishing it. any help appreciated
04-18-2017, 02:41 PM
#2
Instructor
Member Since: Oct 2013
Location: Fond Du lac Wisconsin
Posts: 213
Likes: 0
Received 23 Likes
on
23 Posts
A common cause is a poor ground connection. Trace the wire back from the seat belt clip . Remove the lug ,clean and re-install. Another cause could be a broken wire.
The following users liked this post:
badrabbit (04-19-2017)
04-18-2017, 02:53 PM
#3
Do you have an AIR BAG LIGHT also or has someone maybe removed the bulb for that? If you have an SIR error the cluster SEAT BELT light is also on until one or both errors are corrected.
How long have you had the car?
What does the car do for the "BULB CHECK" at "KEY ON"?
Lots of preliminary checks before you go investigating.
How long have you had the car?
What does the car do for the "BULB CHECK" at "KEY ON"?
Lots of preliminary checks before you go investigating.
04-18-2017, 04:28 PM
#4
Race Director
Member Since: Jan 2000
Location: Owings Mills, MD 21117
Posts: 16,872
Likes: 0
Received 3 Likes
on
3 Posts
Do you have an AIR BAG LIGHT also or has someone maybe removed the bulb for that? If you have an SIR error the cluster SEAT BELT light is also on until one or both errors are corrected.
How long have you had the car?
What does the car do for the "BULB CHECK" at "KEY ON"?
Lots of preliminary checks before you go investigating.
How long have you had the car?
What does the car do for the "BULB CHECK" at "KEY ON"?
Lots of preliminary checks before you go investigating.
04-18-2017, 05:47 PM
#5
OP -If you get an INFL REST light for the KEY-ON "BULB CHECK" and it goes out after the expected 5 seconds then you can assume the SIR is OK and you're only concerned with the FASTEN SEAT BELT light and you can move to the buckle switch. If you have no INF REST light for the "BULB CHECK" at all, then it would be safe to assume that there's an SIR CODE and the FASTEN SEAT BELT won't go out until the SIR is repaired or you elect to remove that bulb also.
04-20-2017, 09:03 PM
#6
Pro
This issue can also be linked to corrosion between the frame rails and SIR impact sensors resulting in a bad ground. There is a TSB ,#90-436-9j (11/07/1991), for this issue.
04-21-2017, 02:52 AM
#7
04-22-2017, 02:01 PM
#9
More than likely the bulb has been removed from the DIC. Replace it and then you can start diagnostics of the system.
08-17-2017, 03:35 PM
#10
Having similar issues myself as badrabit, would really appreciate some hints since the inspection is needed before I could enjoy the roads.
I have read through many threats from here and elsewhere, but got no real clarity on 2 main topics:
1) seat belt light is and stays on (no warning sounds though, key and lights-on sounds are working)
2) error codes
First things first:
- Seat belt light stays on
- Seems like someone took of the INFL/REST lamp since there is never light on that
--> but by checking the error codes - all seems good!? Could this still be the notorious frame sensor grounding issue even though there is no codes?
I have also had a look underneath both seats to check if any wire/connector would be lose or damaged - seems not to be the case.
Didn't found the "***-print" sensors from passenger side as someone pointed out for possible cause...
Only minor deviation I have found so far is in seat belt buckles: on driver side there seems to be small yellow tongue upwards between the locking hole. This comes quite much above the release mechanism, much more than passenger side. Passenger side has something similar, but it's black and much more shorter... Additionally this driver side tongue tilts backwards while pushed with screw driver, passenger side won't move at all... Haven't yet had a chance to check what this might indicate...if nothing.
Then regarding error codes:
Often I see the instruction to follow accurately some 3sec sequences to reset the codes. Is this different level of reset or for different year/model than the "code reset via display"? Somewhere was instructed to go to module 1.7 and/or 4.7 and then press ENG/MET(?) -- or something similar.
Looking forward to hit the roads i.e. getting some help first.
Thanx.
I have read through many threats from here and elsewhere, but got no real clarity on 2 main topics:
1) seat belt light is and stays on (no warning sounds though, key and lights-on sounds are working)
2) error codes
First things first:
- Seat belt light stays on
- Seems like someone took of the INFL/REST lamp since there is never light on that
--> but by checking the error codes - all seems good!? Could this still be the notorious frame sensor grounding issue even though there is no codes?
I have also had a look underneath both seats to check if any wire/connector would be lose or damaged - seems not to be the case.
Didn't found the "***-print" sensors from passenger side as someone pointed out for possible cause...
Only minor deviation I have found so far is in seat belt buckles: on driver side there seems to be small yellow tongue upwards between the locking hole. This comes quite much above the release mechanism, much more than passenger side. Passenger side has something similar, but it's black and much more shorter... Additionally this driver side tongue tilts backwards while pushed with screw driver, passenger side won't move at all... Haven't yet had a chance to check what this might indicate...if nothing.
Then regarding error codes:
Often I see the instruction to follow accurately some 3sec sequences to reset the codes. Is this different level of reset or for different year/model than the "code reset via display"? Somewhere was instructed to go to module 1.7 and/or 4.7 and then press ENG/MET(?) -- or something similar.
Looking forward to hit the roads i.e. getting some help first.
Thanx.
08-17-2017, 08:30 PM
#11
Technical Service Bulletin Number: 90-436-9J - (11/07/1991)
1990: Service Bulletin: SIR Diagnostics and Procedures to Prevent Codes 16 and 26 Due to Corrosion
Subject: SERVICE MAN. UPDATE SEC.9J A/B REV. SIR DIAGNOSTIC PROCEDURE
Model and Year: 1990 CORVETTE
Source: Chevrolet Service Bulletin
Bulletin Number: 90-436-9J - (11/07/1991)
Some 1990 Corvettes have set SIR Sensor Codes 16 and 26. The DERM has detected an unacceptably high resistance between the SIR sensor and the frame rail, most likely due to a buildup of corrosion on the mounting surfaces. New service procedures have been developed to remove the corrosion and help prevent it from building up again. Removal and installation procedures, revised to address the corrosion issue, are attached. Please use these new procedures for all 1990 Corvette SIR Code 16 and Code 26 situations.
IMPORTANT! - The corrosion condition and repair procedures apply only to 1990 Corvette; 1991 and subsequent vehicles do not set sensor codes due to this condition.
The new procedures require the use of a special grease (P/N 12345579) and two external-tooth lock washers (P/N 11501869 - 8 mm, P/N 121753 - 6 mm) for the sensor mounting bolts.
Along with the new procedures, please remember the following:
1. The "SIR Diagnostic System Check" in Section 9J-A must be the starting point of any SIR diagnostics. The "SIR Diagnostic System Check" will verify proper "INFL REST" warning lamp operation and will lead you to the correct chart to diagnose any SIR faults. Bypassing these procedures may result in extended diagnostic time, incorrect diagnosis, and incorrect parts replacement.
2. If both Code 15 and 16 (or 25 and 26) are set, use the Code 16(26) diagnosis chart first. Then, if Code 15(25) resets after the Code 16(26) is corrected, perform the Code 15(25) diagnosis.
3. To clear 1990 Corvette SIR codes, use the Tech 1 (part number T1 or 94-00101-A) with the 1991 Body Systems Cartridge (TKO4040A) and 1990 Dual UART/SIR Adapter (TA00065). The 1991 Body Systems Cartridge must be used because the 1990 Body Systems Cartridge has no SIR code-clearing capabilities for the 1990 Corvette.
If the Tech 1, cartridge, and adapter are not available, codes can be cleared by grounding Terminal "K" of the ALDL connector as called out below under "ALDL Code-Clearing Technique". If using the ALDL procedure, be sure to follow it completely and exactly; codes can be difficult to clear using this method if the procedure is not carefully followed.
4. If the ignition is turned "ON" while any part of the 199O Corvette SIR system is disconnected, a code will set and remain set, even if the component is reconnected, until cleared by the technician.
ALDL CODE-CLEARING TECHNIQUE
When using this code-clearing technique, a digital wristwatch can be quite helpful. The timing sequence discussed below is very important to successfully clearing codes. The watch can help you with timing the 3-second intervals more exactly.
1.Turn ignition "OFF".
2. Ground ALDL terminal "K".
3. Turn ignition "ON". Do not start the car however.
4. Wait for codes to begin flashing (approximately 5 seconds). When codes begin flashing, unground ALDL terminal "K" for 3 seconds +/- 1/2 second.
5. After ungrounding terminal "K" as described in Step 4, ground it again for 3 seconds +/- 1/2 second.
6. Unground ALDL terminal "K", and wait 10 seconds. Before turning ignition "OFF", ground terminal "K" again and verify that Code 12 flashes six (6) times.
If Code 12 does not flash six (6) times, codes have not been cleared properly. Begin clearing procedure again starting with Step 1.
CODE 16 FRONT SENSOR #1 (LH) (SENSOR FAULT) Circuit Description: In a frontal crash of sufficient force, the Front Discriminating Sensor Switch closes, providing a path to ground for the deployment loop current. The sensor contains additional circuitry, used by the DERM for diagnostics. If the DERM measures more than a certain resistance value between the redundant ground circuit and the DERM's own ground, Code 16 will set. This code will also set if the DERM measures less than a certain resistance between the sensor feed circuit and B + or the diagnostic return circuit and B +.
Severe corrosion under the sensor mounting bracket may cause a Code 16. Refer to "Left Sensor" on attached pages to remove sensor, inspect for corrosion, and correct corrosion if found. "Left Sensor" also instructs on use of special grease and washers to help prevent recurrence of Code 16 due to corrosion.
The Fasten Seat Belt indicator will stay "ON" continuously when an SIR code has been set.
If power is applied to the SIR system while any component is not properly connected, an additional code will be set for the disconnected SIR component.
CODE 26 FRONT SENSOR #2 (RH) (SENSOR FAULT) Circuit Description: In a frontal crash of sufficient force, the Front Discriminating Sensor switch closes, providing a path to ground for the deployment loop current. The sensor contains additional circuitry, used by the DERM for diagnostics. If the DERM measures more than a certain resistance value between the redundant ground circuit and the DERM's own ground, Code 26 will set. This code will also set if the DERM measures less than a certain resistance between the sensor feed circuit and B + or the diagnostic return circuit and B +.
If a Code 26 has set, a Code 25 may also be set.
Severe corrosion under the sensor mounting bracket may cause a Code 26. Refer to "Right Sensor" to remove sensor, inspect for corrosion, and correct corrosion if found. "Right Sensor" also instructs on use of special grease and washers to help prevent recurrence of Code 26 due to corrosion.
The Fasten Seat Belt indicator will stay "ON" continuously when an SIR code has been set.
If power is applied to the SIR system while any component is not properly connected, an additional code will be set for the disconnected SIR component.
FORWARD DISCRIMINATING SENSORS Caution should be used to assure proper location of sensors to the front frame rails. The keying of the sensors to the frame rails through the differently sized mounting bolt holes in the sensor mounting plate should never be modified in the field.
CAUTION: Be very careful when handling a sensor. Never strike or jar a sensor. If you do, it could cause deployment and result in personal injury or improper operation of the Supplemental Inflatable Restraint (SIR) system. All sensor mounting bolts must be carefully torqued to assure proper sensor operation. Never power up the SIR system when any sensor is not rigidly attached to the vehicle, since the sensor is easily activated when not attached and could result in a deployment.
LEFT SENSOR
CAUTION: The following procedures must be followed in the order listed to temporarily disable the Supplemental Inflatable Restraint (SIR) system and prevent false diagnostic codes from setting. Failure to follow this procedure could result in possible air bag deployment, personal injury, or unneeded SIR system repairs.
Remove or Disconnect
1. Turn ignition switch "OFF."
2. Left sound insulator; refer to INSTRUMENT PANEL, GAGES, & CONSOLE (SECTION 8C).
3. Connector Position Assurance (CPA) and yellow two-way SIR connector at base of steering column.
4. Battery; refer to BATTERY (SECTION 6D1).
5. ECM and support; refer to DRIVEABILITY AND EMISSIONS 9SECTION 6E3).
6. Sensor mounting bolts.
7. Sensor electrical connection from retainer; disconnect connection.
8. Sensor from vehicle.
IMPORTANT
Clean Sensor mounting bracket surface, frame rail mounting surface, and mounting bolts and holes to remove any paint or corrosion that might interfere with a good electrical ground.
CAUTION Proper operation of the sensors and Supplemental inflatable Restraint (SIR) system requires that repairs to the vehicle structure return it to its original production configuration. Deployment requires, at a minimum, replacement of the DERM, both forward discriminating sensors, the SIR Coil Assembly, and the Inflator Module. Any visible damage to the sensors, DERM, and/or the DERM mounting brackets requires replacement, and the steering wheel must be dimensionally inspected, whether deployment occurred or not.
Install or Connect
1. Apply a thin layer of special grease P/N 12345579 to the frame rail mounting surface and the mounting flange of the sensor. Do not apply the grease to the mounting bolts or holes.
2. Forward discriminating sensor, with arrow pointing toward front of vehicle.
3. External tooth lock washers, P/N 11501869 (8 mm) and 121753 (6 mm) to mounting bolts.
4. Sensor mounting bolts. Ensure that washers are between bolt head and senor mounting flange, not between mounting flange and frame rail. Tighten Front (13 mm head) bolt to 25 N.m (19 lb. ft.) - Rear (10 mm head) bolt to 14 N.m (125 lb. in.)
5. Sensor electrical connection, then clip completed connection into retainer.
6. ECM and support; refer to DRIVEABILITY AND EMISSIONS (SECTION 6E3).
7. Battery; refer to BATTERY (SECTION 6D1).
8. Yellow two-way SIR connector at base of steering column and Connector Position Assurance (CPA).
9. Left sound insulator; refer to INSTRUMENT PANEL, GAGES & CONSOLE (SECTION 8C).
10. Perform "SIR Diagnostic System Check" as outlines in SIR SYSTEM DIAGNOSIS (SECTION 9JA).
RIGHT SENSOR
CAUTION The following procedures must be followed in the order listed to temporarily disable the Supplemental Inflatable Restraint (SIR) system and prevent false diagnostic codes from setting. Failure to follow this procedure could result in possible air bag deployment, personal injury, or unneeded SIR system repairs.
Remove or Disconnect
1. Turn ignition switch "OFF."
2. Left sound insulator; refer to INSTRUMENT PANEL, GAGES & CONSOLE (SECTION 8C).
3. Connector Position Assurance (CPA) and yellow two-way SIR connector at base of steering column.
4. Six front right-side rocker panel retaining screws.
5. Right-side front fender "grill panel" retaining bolts, remove fender.
6. Peel back rear portion of wheelhouse-to-hood seal.
7. Right-side lower wheelhouse retaining bolts; remove lower wheelhouse.
8. Two front windshield washer reservoir retaining bolts.
9. Loosen remaining washer reservoir bolt; rotate reservoir to access sensor.
10. Sensor mounting bolts.
11. Sensor electrical connection from retainer; disconnect connection.
12. Sensor from vehicle.
IMPORTANT
Clean Sensor mounting bracket surface, frame rail mounting surface, and mounting bolts and holes to remove any paint or corrosion that might interfere with a good electrical ground.
CAUTION: Proper operation of the sensors and Supplemental Inflatable Restraint (SIR) system requires that repairs to the vehicle structure return it to its original production configuration. Deployment requires, at a minimum, replacement of the DERM, both forward discriminating sensors, the SIR coil Assembly, and the Inflator Module. Any visible damage to the sensors, DERM, and/or the DERM mounting brackets requires replacement, and the steering wheel must be dimensionally inspected, whether deployment occurred or not.
Proper operation of the forward discriminating sensor requires the sensor be rigidly attached to the vehicle structure and that the arrow on the sensor be pointing toward the front of the vehicle.
Install or Connect
1. Apply a thin layer of special grease P/N 12345579 to the frame rail mounting surface and the mounting flange of the sensor. Do not apply the grease to the mounting bolts or holes.
2. Forward discriminating sensor, with arrow pointing toward front of vehicle.
3. External tooth lock washers, P/N 11501869 (8 mm) and 121753 (6 mm) to mounting bolts.
4. Sensor mounting bolts. Ensure that washers are between bolt head and sensor mounting flange, not between mounting flange and frame rail. Tighten Front (13 mm head) bolt to 25 N.m (19 lb. ft.) - Rear (10 mm head) bolt to 14 N.m (125 lb. ft.)
5. Sensor electrical connection, then clip completed connection into retainer.
6. Position windshield washer reservoir; install retaining bolts.
Tighten Reservoir mounting screws to 10 N.m (89 lb. in.)
7. Lower wheelhouse and retaining bolts. Tighten Wheelhouse to "U"-nut bolts to 6 N.m (54 lb. in.). - Wheelhouse to frame member bolts to 9 N.m (80 lb. in.).
8. Reposition wheelhouse -to-hood seal.
9. Right-side front fender ("grill panel"); install retaining bolts.
10. Six front right-side rocker panel retaining screws.
11. Yellow two-way SIR connector at base of steering column and Connector Position Assurance (CPA).
12. Left sound insulator; refer to INSTRUMENT PANEL, GAGES & CONSOLE (SECTION 8C).
13. Perform "SIR Diagnostic System Check" as outlined in SIR SYSTEM DIAGNOSIS (SECTION 9JA).
**************************************** ****************
Subject: SERVICE MAN. UPDATE SEC.9J A/B REV. SIR DIAGNOSTIC PROCEDURE
Model and Year: 1990 CORVETTE
Source: Chevrolet Service Bulletin
Bulletin Number: 90-436-9J - (11/07/1991)
Some 1990 Corvettes have set SIR Sensor Codes 16 and 26. The DERM has detected an unacceptably high resistance between the SIR sensor and the frame rail, most likely due to a buildup of corrosion on the mounting surfaces. New service procedures have been developed to remove the corrosion and help prevent it from building up again. Removal and installation procedures, revised to address the corrosion issue, are attached. Please use these new procedures for all 1990 Corvette SIR Code 16 and Code 26 situations.
IMPORTANT! - The corrosion condition and repair procedures apply only to 1990 Corvette; 1991 and subsequent vehicles do not set sensor codes due to this condition.
The new procedures require the use of a special grease (P/N 12345579) and two external-tooth lock washers (P/N 11501869 - 8 mm, P/N 121753 - 6 mm) for the sensor mounting bolts.
Along with the new procedures, please remember the following:
1. The "SIR Diagnostic System Check" in Section 9J-A must be the starting point of any SIR diagnostics. The "SIR Diagnostic System Check" will verify proper "INFL REST" warning lamp operation and will lead you to the correct chart to diagnose any SIR faults. Bypassing these procedures may result in extended diagnostic time, incorrect diagnosis, and incorrect parts replacement.
2. If both Code 15 and 16 (or 25 and 26) are set, use the Code 16(26) diagnosis chart first. Then, if Code 15(25) resets after the Code 16(26) is corrected, perform the Code 15(25) diagnosis.
3. To clear 1990 Corvette SIR codes, use the Tech 1 (part number T1 or 94-00101-A) with the 1991 Body Systems Cartridge (TKO4040A) and 1990 Dual UART/SIR Adapter (TA00065). The 1991 Body Systems Cartridge must be used because the 1990 Body Systems Cartridge has no SIR code-clearing capabilities for the 1990 Corvette.
If the Tech 1, cartridge, and adapter are not available, codes can be cleared by grounding Terminal "K" of the ALDL connector as called out below under "ALDL Code-Clearing Technique". If using the ALDL procedure, be sure to follow it completely and exactly; codes can be difficult to clear using this method if the procedure is not carefully followed.
4. If the ignition is turned "ON" while any part of the 199O Corvette SIR system is disconnected, a code will set and remain set, even if the component is reconnected, until cleared by the technician.
ALDL CODE-CLEARING TECHNIQUE
When using this code-clearing technique, a digital wristwatch can be quite helpful. The timing sequence discussed below is very important to successfully clearing codes. The watch can help you with timing the 3-second intervals more exactly.
1.Turn ignition "OFF".
2. Ground ALDL terminal "K".
3. Turn ignition "ON". Do not start the car however.
4. Wait for codes to begin flashing (approximately 5 seconds). When codes begin flashing, unground ALDL terminal "K" for 3 seconds +/- 1/2 second.
5. After ungrounding terminal "K" as described in Step 4, ground it again for 3 seconds +/- 1/2 second.
6. Unground ALDL terminal "K", and wait 10 seconds. Before turning ignition "OFF", ground terminal "K" again and verify that Code 12 flashes six (6) times.
If Code 12 does not flash six (6) times, codes have not been cleared properly. Begin clearing procedure again starting with Step 1.
CODE 16 FRONT SENSOR #1 (LH) (SENSOR FAULT) Circuit Description: In a frontal crash of sufficient force, the Front Discriminating Sensor Switch closes, providing a path to ground for the deployment loop current. The sensor contains additional circuitry, used by the DERM for diagnostics. If the DERM measures more than a certain resistance value between the redundant ground circuit and the DERM's own ground, Code 16 will set. This code will also set if the DERM measures less than a certain resistance between the sensor feed circuit and B + or the diagnostic return circuit and B +.
Severe corrosion under the sensor mounting bracket may cause a Code 16. Refer to "Left Sensor" on attached pages to remove sensor, inspect for corrosion, and correct corrosion if found. "Left Sensor" also instructs on use of special grease and washers to help prevent recurrence of Code 16 due to corrosion.
The Fasten Seat Belt indicator will stay "ON" continuously when an SIR code has been set.
If power is applied to the SIR system while any component is not properly connected, an additional code will be set for the disconnected SIR component.
CODE 26 FRONT SENSOR #2 (RH) (SENSOR FAULT) Circuit Description: In a frontal crash of sufficient force, the Front Discriminating Sensor switch closes, providing a path to ground for the deployment loop current. The sensor contains additional circuitry, used by the DERM for diagnostics. If the DERM measures more than a certain resistance value between the redundant ground circuit and the DERM's own ground, Code 26 will set. This code will also set if the DERM measures less than a certain resistance between the sensor feed circuit and B + or the diagnostic return circuit and B +.
If a Code 26 has set, a Code 25 may also be set.
Severe corrosion under the sensor mounting bracket may cause a Code 26. Refer to "Right Sensor" to remove sensor, inspect for corrosion, and correct corrosion if found. "Right Sensor" also instructs on use of special grease and washers to help prevent recurrence of Code 26 due to corrosion.
The Fasten Seat Belt indicator will stay "ON" continuously when an SIR code has been set.
If power is applied to the SIR system while any component is not properly connected, an additional code will be set for the disconnected SIR component.
FORWARD DISCRIMINATING SENSORS Caution should be used to assure proper location of sensors to the front frame rails. The keying of the sensors to the frame rails through the differently sized mounting bolt holes in the sensor mounting plate should never be modified in the field.
CAUTION: Be very careful when handling a sensor. Never strike or jar a sensor. If you do, it could cause deployment and result in personal injury or improper operation of the Supplemental Inflatable Restraint (SIR) system. All sensor mounting bolts must be carefully torqued to assure proper sensor operation. Never power up the SIR system when any sensor is not rigidly attached to the vehicle, since the sensor is easily activated when not attached and could result in a deployment.
LEFT SENSOR
CAUTION: The following procedures must be followed in the order listed to temporarily disable the Supplemental Inflatable Restraint (SIR) system and prevent false diagnostic codes from setting. Failure to follow this procedure could result in possible air bag deployment, personal injury, or unneeded SIR system repairs.
Remove or Disconnect
1. Turn ignition switch "OFF."
2. Left sound insulator; refer to INSTRUMENT PANEL, GAGES, & CONSOLE (SECTION 8C).
3. Connector Position Assurance (CPA) and yellow two-way SIR connector at base of steering column.
4. Battery; refer to BATTERY (SECTION 6D1).
5. ECM and support; refer to DRIVEABILITY AND EMISSIONS 9SECTION 6E3).
6. Sensor mounting bolts.
7. Sensor electrical connection from retainer; disconnect connection.
8. Sensor from vehicle.
IMPORTANT
Clean Sensor mounting bracket surface, frame rail mounting surface, and mounting bolts and holes to remove any paint or corrosion that might interfere with a good electrical ground.
CAUTION Proper operation of the sensors and Supplemental inflatable Restraint (SIR) system requires that repairs to the vehicle structure return it to its original production configuration. Deployment requires, at a minimum, replacement of the DERM, both forward discriminating sensors, the SIR Coil Assembly, and the Inflator Module. Any visible damage to the sensors, DERM, and/or the DERM mounting brackets requires replacement, and the steering wheel must be dimensionally inspected, whether deployment occurred or not.
Install or Connect
1. Apply a thin layer of special grease P/N 12345579 to the frame rail mounting surface and the mounting flange of the sensor. Do not apply the grease to the mounting bolts or holes.
2. Forward discriminating sensor, with arrow pointing toward front of vehicle.
3. External tooth lock washers, P/N 11501869 (8 mm) and 121753 (6 mm) to mounting bolts.
4. Sensor mounting bolts. Ensure that washers are between bolt head and senor mounting flange, not between mounting flange and frame rail. Tighten Front (13 mm head) bolt to 25 N.m (19 lb. ft.) - Rear (10 mm head) bolt to 14 N.m (125 lb. in.)
5. Sensor electrical connection, then clip completed connection into retainer.
6. ECM and support; refer to DRIVEABILITY AND EMISSIONS (SECTION 6E3).
7. Battery; refer to BATTERY (SECTION 6D1).
8. Yellow two-way SIR connector at base of steering column and Connector Position Assurance (CPA).
9. Left sound insulator; refer to INSTRUMENT PANEL, GAGES & CONSOLE (SECTION 8C).
10. Perform "SIR Diagnostic System Check" as outlines in SIR SYSTEM DIAGNOSIS (SECTION 9JA).
RIGHT SENSOR
CAUTION The following procedures must be followed in the order listed to temporarily disable the Supplemental Inflatable Restraint (SIR) system and prevent false diagnostic codes from setting. Failure to follow this procedure could result in possible air bag deployment, personal injury, or unneeded SIR system repairs.
Remove or Disconnect
1. Turn ignition switch "OFF."
2. Left sound insulator; refer to INSTRUMENT PANEL, GAGES & CONSOLE (SECTION 8C).
3. Connector Position Assurance (CPA) and yellow two-way SIR connector at base of steering column.
4. Six front right-side rocker panel retaining screws.
5. Right-side front fender "grill panel" retaining bolts, remove fender.
6. Peel back rear portion of wheelhouse-to-hood seal.
7. Right-side lower wheelhouse retaining bolts; remove lower wheelhouse.
8. Two front windshield washer reservoir retaining bolts.
9. Loosen remaining washer reservoir bolt; rotate reservoir to access sensor.
10. Sensor mounting bolts.
11. Sensor electrical connection from retainer; disconnect connection.
12. Sensor from vehicle.
IMPORTANT
Clean Sensor mounting bracket surface, frame rail mounting surface, and mounting bolts and holes to remove any paint or corrosion that might interfere with a good electrical ground.
CAUTION: Proper operation of the sensors and Supplemental Inflatable Restraint (SIR) system requires that repairs to the vehicle structure return it to its original production configuration. Deployment requires, at a minimum, replacement of the DERM, both forward discriminating sensors, the SIR coil Assembly, and the Inflator Module. Any visible damage to the sensors, DERM, and/or the DERM mounting brackets requires replacement, and the steering wheel must be dimensionally inspected, whether deployment occurred or not.
Proper operation of the forward discriminating sensor requires the sensor be rigidly attached to the vehicle structure and that the arrow on the sensor be pointing toward the front of the vehicle.
Install or Connect
1. Apply a thin layer of special grease P/N 12345579 to the frame rail mounting surface and the mounting flange of the sensor. Do not apply the grease to the mounting bolts or holes.
2. Forward discriminating sensor, with arrow pointing toward front of vehicle.
3. External tooth lock washers, P/N 11501869 (8 mm) and 121753 (6 mm) to mounting bolts.
4. Sensor mounting bolts. Ensure that washers are between bolt head and sensor mounting flange, not between mounting flange and frame rail. Tighten Front (13 mm head) bolt to 25 N.m (19 lb. ft.) - Rear (10 mm head) bolt to 14 N.m (125 lb. ft.)
5. Sensor electrical connection, then clip completed connection into retainer.
6. Position windshield washer reservoir; install retaining bolts.
Tighten Reservoir mounting screws to 10 N.m (89 lb. in.)
7. Lower wheelhouse and retaining bolts. Tighten Wheelhouse to "U"-nut bolts to 6 N.m (54 lb. in.). - Wheelhouse to frame member bolts to 9 N.m (80 lb. in.).
8. Reposition wheelhouse -to-hood seal.
9. Right-side front fender ("grill panel"); install retaining bolts.
10. Six front right-side rocker panel retaining screws.
11. Yellow two-way SIR connector at base of steering column and Connector Position Assurance (CPA).
12. Left sound insulator; refer to INSTRUMENT PANEL, GAGES & CONSOLE (SECTION 8C).
13. Perform "SIR Diagnostic System Check" as outlined in SIR SYSTEM DIAGNOSIS (SECTION 9JA).
**************************************** ****************
Last edited by Joe C; 08-18-2017 at 03:05 AM.
The following users liked this post:
Tane (08-19-2017)
08-18-2017, 01:02 PM
#12
Having similar issues myself as badrabit, would really appreciate some hints since the inspection is needed before I could enjoy the roads.
I have read through many threats from here and elsewhere, but got no real clarity on 2 main topics:
1) seat belt light is and stays on (no warning sounds though, key and lights-on sounds are working)
2) error codes
First things first:
- Seat belt light stays on
- Seems like someone took of the INFL/REST lamp since there is never light on that
--> but by checking the error codes - all seems good!? Could this still be the notorious frame sensor grounding issue even though there is no codes?
Then regarding error codes:
Often I see the instruction to follow accurately some 3sec sequences to reset the codes. Is this different level of reset or for different year/model than the "code reset via display"? Somewhere was instructed to go to module 1.7 and/or 4.7 and then press ENG/MET(?) -- or something similar.
I have read through many threats from here and elsewhere, but got no real clarity on 2 main topics:
1) seat belt light is and stays on (no warning sounds though, key and lights-on sounds are working)
2) error codes
First things first:
- Seat belt light stays on
- Seems like someone took of the INFL/REST lamp since there is never light on that
--> but by checking the error codes - all seems good!? Could this still be the notorious frame sensor grounding issue even though there is no codes?
Then regarding error codes:
Often I see the instruction to follow accurately some 3sec sequences to reset the codes. Is this different level of reset or for different year/model than the "code reset via display"? Somewhere was instructed to go to module 1.7 and/or 4.7 and then press ENG/MET(?) -- or something similar.
And the reset procedure has nothing to do with going into the CCM diagnostics via the gauge cluster.
08-19-2017, 08:35 AM
#13
(my 2-cents, FWIW) -- 9 times out of 10, it's a grounding issue with the sensors. i'm guessing it has a lot to do with the base of the sensor being aluminum, and the steel frame of the car. there's a natural corrosion between dissimilar metals, first you'll need to repair associated indicator lights. once you have the "INFL REST" indicator light sorted, clean the base of both sensors, and the frame. apply a light coat of CONDUCTIVE grease to both surfaces. do not use di-electric grease. fabricate a secondary ground strap from 14 or 16 gauge wire with ring style crimp-lugs, and double ground both sensors. secure one end of the strap to the sensor mounting fastener, and find a place on the frame and secure the other end. use grounding washers with conductive grease. clear your codes per the TSB. should solve your problems -
Thank you JoeC for sharing the detailed and clear instructions. Will for sure follow at some point if/when getting convinced of this task...
Why I am not unfortunately yet fully convinced is that I don't have any codes. Display only shows C12.
And as I read the detailed article it seems that all information is based on the codes. It also seems fairly logical since such an option exists.
Any good idea where to check the remaining 1/10 issue?
08-19-2017, 08:37 AM
#14
Seems logical and reasonable enough. With this way I got only the initial C12 out of my Corvette. Module 1 and 4 showed only dashes and module 9 does not exist (read somewhere that 9th was introduced first for 91 or 92's).
Is there some reasons why this would not work or would be different in 90's Corvette?
...just came to my mind that probably with my luck, there is place A, B and C to look for different errors and I am naturally in wrong place :-D
Last edited by Tane; 08-19-2017 at 08:46 AM.
08-19-2017, 08:40 AM
#15
In a 90, the seat belt buckle switch will not keep the seat belt light on. Actually, the buckle switch only affects the chime. The light comes on for about 5 seconds with key-on, then goes out. If the belt isn't buckled while the light is on during this 5 second period, the chime will sound. If the belt is buckeled, the chime won't sound, but the light is on for the 5 seconds.
08-19-2017, 01:29 PM
#16
There's several TSB's for the '90 that are SIR related. I believe maybe 3. The OP shouldn't need to be concerned with the TSB until he mentions the KEY ON results. That would dictate his next move.
OP -If you get an INFL REST light for the KEY-ON "BULB CHECK" and it goes out after the expected 5 seconds then you can assume the SIR is OK and you're only concerned with the FASTEN SEAT BELT light and you can move to the buckle switch. If you have no INF REST light for the "BULB CHECK" at all, then it would be safe to assume that there's an SIR CODE and the FASTEN SEAT BELT won't go out until the SIR is repaired or you elect to remove that bulb also.
OP -If you get an INFL REST light for the KEY-ON "BULB CHECK" and it goes out after the expected 5 seconds then you can assume the SIR is OK and you're only concerned with the FASTEN SEAT BELT light and you can move to the buckle switch. If you have no INF REST light for the "BULB CHECK" at all, then it would be safe to assume that there's an SIR CODE and the FASTEN SEAT BELT won't go out until the SIR is repaired or you elect to remove that bulb also.
08-19-2017, 03:02 PM
#17
Last edited by Joe C; 08-19-2017 at 03:02 PM.
08-23-2017, 02:16 PM
#18
Well well well...
Took the DIC apart and *look at that*, not only that no-one bothered to take the INFL/REST light out, they saw it better to smash it...
So, next up is changing the bulb from some other position and start to move towards the sensor job.
Took the DIC apart and *look at that*, not only that no-one bothered to take the INFL/REST light out, they saw it better to smash it...
So, next up is changing the bulb from some other position and start to move towards the sensor job.
08-23-2017, 04:30 PM
#19
Typical C4 owner. Not only do we do a cheap job fixing a problem, we destroy the part as well.
Last edited by ChumpVette; 08-23-2017 at 04:30 PM.
09-10-2017, 03:06 PM
#20
you can take it in for service all you want, but nothing's going to happen. first of all, the tech will read the code(s), and tell you one or both sensors need replaced. since the sensors have been discontinued and are no longer available - even at the aftermarket level, your service center will tell you there's nothing they can do. they don't want to repair anything, all they want to do is replace parts. two things can happen, as you said, ignore it (the light), or clean the grounds per the TSB, and hope for the best. as I said, 9 times of 10, it's a grounding issue.
Took out both of the sensors and did the things instructed. Thank you JoeC.
Wasn't actually that bad as I expected. Also the code reset went straight through and....seat belt light AND Infl/Rest light went off when I started the car, felt good. For the first time ever, the dash was dark!
The happiness, singing and dancing didn't last long though, roughly 5 sec or so...
Both lights came back
The reset got rid of most SIR errors 16,26,33,34,42 but annoyingly 35 was left.
Now, as clueless as ever, starting the hunt of the 35.
Somewhere was mentioned that it should be "Steering column SIR connector", but at least the one next to the column, above the pedals, was firmly connected.
