A/C problem, after battery replacement.
Thread Starter
8th Gear
Joined: Dec 2000
Posts: 8
Likes: 0
From: sunny fla.
A/C problem, after battery replacement.
Compressor runs, but vents blow heat.
Same thing happened 7 years ago on my 98 pace car the last time I put in a new battery.
Y'all said pull fuses 18 n' 27 and it solved the problem. But it doesn't change anything this time.
Is there another home fix I can try, before paying someone to look at it?
Thanks
Same thing happened 7 years ago on my 98 pace car the last time I put in a new battery.
Y'all said pull fuses 18 n' 27 and it solved the problem. But it doesn't change anything this time.
Is there another home fix I can try, before paying someone to look at it?
Thanks
Tech Contributor
Joined: Dec 1999
Posts: 32,910
Likes: 2,402
From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
For starters,,, read and post your DTCs. That will tell us what the mystery is:
READING YOUR Engine Diagnostic Trouble Codes (DTC)
This procedure should be carried out any time you experience a problem with your C5. Most inexpensive store bought aftermarket code readers will ONLY read power train DTC’s. Reading the DTC’s with the C5 built in code reader will allow you to read ALL the modules in the vehicle.
The Diagnostic Display Mode is entered with the following procedure:
1) Turn on the ignition but don't start the engine.
2) Press the RESET button to turn off any warning messages. (i.e. door open, trunk open ect)
3) Press and hold the OPTIONS button
4) While holding OPTIONS, press FUEL button four times within a 10 -second period.
Initially, the on-board diagnostics go into an Automatic Mode which will cycle through each module and shows diagnostic codes in a pre-set sequence: PCM - TCS - RTD - BCM - IPC - RADIO - HVAC - LDCM - RDCM - SCM - RFA. All codes will be displayed for each module. ( i.e. PCM = 4 codes) If none are present in a given module, you will see No More Codes on the display.
There are two types of diagnostic codes, Current and History designated with a letter suffix, “C” or “H”. A current code indicates a malfunction is present in the module displaying data. A history code indicates a problem existed sometime in the last 40 or 50 ignition cycles. When not accompanied by a current code of the same number, it's potential evidence of a previous problem, now resolved, that was not removed by clearing the codes. More likely it's an indication of an intermittent malfunction.
Intermittent codes are the most challenging of the diagnostics. An intermittent code may have happened once, may have happened more than once but is inconsistent or may be happening on a regular basis but not at the time the codes are displayed. History codes can also be caused by a current malfunction in a system that is not operating at the time codes are displayed. An example is the rear window defogger which doesn't operate until the Body Control Module detects engine rpm. For history codes set by a module that does not operate with the key on and engine off, a special diagnostic tool called a Scan Tester is necessary to properly diagnose the malfunction.
Once the system has displayed all modules, it goes into the manual mode which allows selection of each module using combinations of Driver Information Center buttons. Manual mode can also be entered during the automatic sequence by pressing any button except E/M. Once the display shows Manual Diagnostics, select a module by pressing the OPTIONS button to go forward or the TRIP button to go back. Once a module is selected, a code is displayed, and if more than one are present; press GAGES to go forward or FUEL to go back.
To exit the diagnostic mode at any time, press E/M. If you want to erase codes in a given module, press RESET To reset the codes once in manual mode, press and hold RESET until it displays NO CODES Press OPTIONS to go to the next module. Repeat the steps until you have reset the codes in all the computer modules.
NOTE!! Only reset the codes IF you want to - it is NOT necessary to do this. Clearing a code does not repair a problem. You are simply erasing the evidence of it in the module's memory. If you clear the code/s, and extinguish the Check Engine Light, your emissions status ready will NOT allow you to pass an emissions test until you have completed the required driving cycles. There are a few body module DTC’s that if set will prevent the module from operating properly. Once the DTC is cleared, the module will return to full function. This is not true for power train DTCs.
If you have never read and cleared your codes, there will probably be a lot of old history DTCs. It is recommended that you clear your codes and see if any come back during a driving cycle. Those are the ones that you need to concentrate on diagnosing.
Once you have the codes, the next question is: What to do with the information?
First, consult the factory service manual. Any serious C5 Do-It-Yourself owner should invest in the Corvette Service Manual of the appropriate model year. The Service Manual is really a requirement if you want to understand and work on your C5.
NOTE and a WARNING. You can read the DTCs while the engine is running. I pull mine up all the time while driving.
WARNING. Don’t become distracted while reading DTCs while your driving and cause an accident!!!!! Use common sense and drive safe.
These are some very good C5 Diagnostic Trouble Code (DTC) explanation web sites!!! They also explain how to read the DTCs
Here are some very good sites that explain what DTC mean:
http://www.gearchatter.com/viewtopic11755.php
http://www.obd-codes.com/trouble_cod...d-ii-codes.php
Make sure to include the H or C suffix when you post your DTCs!!
READING YOUR Engine Diagnostic Trouble Codes (DTC)
This procedure should be carried out any time you experience a problem with your C5. Most inexpensive store bought aftermarket code readers will ONLY read power train DTC’s. Reading the DTC’s with the C5 built in code reader will allow you to read ALL the modules in the vehicle.
The Diagnostic Display Mode is entered with the following procedure:
1) Turn on the ignition but don't start the engine.
2) Press the RESET button to turn off any warning messages. (i.e. door open, trunk open ect)
3) Press and hold the OPTIONS button
4) While holding OPTIONS, press FUEL button four times within a 10 -second period.
Initially, the on-board diagnostics go into an Automatic Mode which will cycle through each module and shows diagnostic codes in a pre-set sequence: PCM - TCS - RTD - BCM - IPC - RADIO - HVAC - LDCM - RDCM - SCM - RFA. All codes will be displayed for each module. ( i.e. PCM = 4 codes) If none are present in a given module, you will see No More Codes on the display.
There are two types of diagnostic codes, Current and History designated with a letter suffix, “C” or “H”. A current code indicates a malfunction is present in the module displaying data. A history code indicates a problem existed sometime in the last 40 or 50 ignition cycles. When not accompanied by a current code of the same number, it's potential evidence of a previous problem, now resolved, that was not removed by clearing the codes. More likely it's an indication of an intermittent malfunction.
Intermittent codes are the most challenging of the diagnostics. An intermittent code may have happened once, may have happened more than once but is inconsistent or may be happening on a regular basis but not at the time the codes are displayed. History codes can also be caused by a current malfunction in a system that is not operating at the time codes are displayed. An example is the rear window defogger which doesn't operate until the Body Control Module detects engine rpm. For history codes set by a module that does not operate with the key on and engine off, a special diagnostic tool called a Scan Tester is necessary to properly diagnose the malfunction.
Once the system has displayed all modules, it goes into the manual mode which allows selection of each module using combinations of Driver Information Center buttons. Manual mode can also be entered during the automatic sequence by pressing any button except E/M. Once the display shows Manual Diagnostics, select a module by pressing the OPTIONS button to go forward or the TRIP button to go back. Once a module is selected, a code is displayed, and if more than one are present; press GAGES to go forward or FUEL to go back.
To exit the diagnostic mode at any time, press E/M. If you want to erase codes in a given module, press RESET To reset the codes once in manual mode, press and hold RESET until it displays NO CODES Press OPTIONS to go to the next module. Repeat the steps until you have reset the codes in all the computer modules.
NOTE!! Only reset the codes IF you want to - it is NOT necessary to do this. Clearing a code does not repair a problem. You are simply erasing the evidence of it in the module's memory. If you clear the code/s, and extinguish the Check Engine Light, your emissions status ready will NOT allow you to pass an emissions test until you have completed the required driving cycles. There are a few body module DTC’s that if set will prevent the module from operating properly. Once the DTC is cleared, the module will return to full function. This is not true for power train DTCs.
If you have never read and cleared your codes, there will probably be a lot of old history DTCs. It is recommended that you clear your codes and see if any come back during a driving cycle. Those are the ones that you need to concentrate on diagnosing.
Once you have the codes, the next question is: What to do with the information?
First, consult the factory service manual. Any serious C5 Do-It-Yourself owner should invest in the Corvette Service Manual of the appropriate model year. The Service Manual is really a requirement if you want to understand and work on your C5.
NOTE and a WARNING. You can read the DTCs while the engine is running. I pull mine up all the time while driving.
WARNING. Don’t become distracted while reading DTCs while your driving and cause an accident!!!!! Use common sense and drive safe.
These are some very good C5 Diagnostic Trouble Code (DTC) explanation web sites!!! They also explain how to read the DTCs
Here are some very good sites that explain what DTC mean:
http://www.gearchatter.com/viewtopic11755.php
http://www.obd-codes.com/trouble_cod...d-ii-codes.php
Make sure to include the H or C suffix when you post your DTCs!!
Thread Starter
8th Gear
Joined: Dec 2000
Posts: 8
Likes: 0
From: sunny fla.
Ok, I can do that.
I'm also dealing with a fuel leak in the area of the drivers side rear wheel.
Taking the car to a friend with a lift this morning.
Thinking its one of the ''quick connects''.
Thanks, Jim
I'm also dealing with a fuel leak in the area of the drivers side rear wheel.
Taking the car to a friend with a lift this morning.
Thinking its one of the ''quick connects''.
Thanks, Jim
Burning Brakes
Joined: Aug 2009
Posts: 816
Likes: 0
From: Virginia Beach Virginia
When I go out in the morning and turn my heat on, (2003 dual climate HVAC) the A/C automatically comes on, if I just press the A/C button it will turn off and I can adjust the fan speed, but when I switch to Defroster it comes back on, when I try to turn it off the button blinks then stays on... And I start allover untill I just give up. I dont want to run the A/C to have heat....any ideas?
Tech Contributor
Joined: Dec 1999
Posts: 32,910
Likes: 2,402
From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
Read the owners manual. 
DEFROST always runs the AC. If your in DEFROST,, you can not shut it off. Blink, means illogical.
Sounds like you have the MEMORY set so that it sets up the AC in a mode that you need to change all the time.
Set EVERYTHING the way that you want it:
AC Mode, Fans, vent positions, AC on or OFF, Radio stations, volume,, etc etc..... Then PRESS and HOLD the MEM1 setting on the door panel. Then do the same for MEM 2.
See if that resolves your issue.
IF,,,,,,,,,,,,, what you set fails to remain set the next day,, Look at your BATTERY. If its weak, it will cause the MEM settings to revert to the factory defaults when you crank the car and battery voltage goes LOW.
BC
DEFROST always runs the AC. If your in DEFROST,, you can not shut it off. Blink, means illogical.
Sounds like you have the MEMORY set so that it sets up the AC in a mode that you need to change all the time.
Set EVERYTHING the way that you want it:
AC Mode, Fans, vent positions, AC on or OFF, Radio stations, volume,, etc etc..... Then PRESS and HOLD the MEM1 setting on the door panel. Then do the same for MEM 2.
See if that resolves your issue.
IF,,,,,,,,,,,,, what you set fails to remain set the next day,, Look at your BATTERY. If its weak, it will cause the MEM settings to revert to the factory defaults when you crank the car and battery voltage goes LOW.
BC
Tech Contributor
Joined: Dec 1999
Posts: 32,910
Likes: 2,402
From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
If you get HEAT when you have cold selected,, here are the possibilities:
The temp damper doors are positioned to the heat position
OR
There isn't any or enough R134 flowing to cool the cooling coils. Are you POSITIVE that the AC clutch is engaged and the compressor is flowing R134?
Feel the cooling lines and see if the large one is cold. If it is cold,, you have an issue with the temp door actuators that position the damper doors.
BC
The temp damper doors are positioned to the heat position
OR
There isn't any or enough R134 flowing to cool the cooling coils. Are you POSITIVE that the AC clutch is engaged and the compressor is flowing R134?
Feel the cooling lines and see if the large one is cold. If it is cold,, you have an issue with the temp door actuators that position the damper doors.
BC
Burning Brakes
Joined: Aug 2009
Posts: 816
Likes: 0
From: Virginia Beach Virginia
Read the owners manual.
DEFROST always runs the AC. If your in DEFROST,, you can not shut it off. Blink, means illogical.
Sounds like you have the MEMORY set so that it sets up the AC in a mode that you need to change all the time.
Set EVERYTHING the way that you want it:
AC Mode, Fans, vent positions, AC on or OFF, Radio stations, volume,, etc etc..... Then PRESS and HOLD the MEM1 setting on the door panel. Then do the same for MEM 2.
See if that resolves your issue.
IF,,,,,,,,,,,,, what you set fails to remain set the next day,, Look at your BATTERY. If its weak, it will cause the MEM settings to revert to the factory defaults when you crank the car and battery voltage goes LOW.
BC
DEFROST always runs the AC. If your in DEFROST,, you can not shut it off. Blink, means illogical.
Sounds like you have the MEMORY set so that it sets up the AC in a mode that you need to change all the time.
Set EVERYTHING the way that you want it:
AC Mode, Fans, vent positions, AC on or OFF, Radio stations, volume,, etc etc..... Then PRESS and HOLD the MEM1 setting on the door panel. Then do the same for MEM 2.
See if that resolves your issue.
IF,,,,,,,,,,,,, what you set fails to remain set the next day,, Look at your BATTERY. If its weak, it will cause the MEM settings to revert to the factory defaults when you crank the car and battery voltage goes LOW.
BC
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Advanced
Joined: Sep 2011
Posts: 79
Likes: 0
From: FL
Ok if u have a problem with the temp door actuators not positioning the damper doors correctly... How do u fix this and where the heck or those components because I've never heard of those words.??? I have a manual Non Dual ac
If you get HEAT when you have cold selected,, here are the possibilities:
The temp damper doors are positioned to the heat position
OR
There isn't any or enough R134 flowing to cool the cooling coils. Are you POSITIVE that the AC clutch is engaged and the compressor is flowing R134?
Feel the cooling lines and see if the large one is cold. If it is cold,, you have an issue with the temp door actuators that position the damper doors.
BC
The temp damper doors are positioned to the heat position
OR
There isn't any or enough R134 flowing to cool the cooling coils. Are you POSITIVE that the AC clutch is engaged and the compressor is flowing R134?
Feel the cooling lines and see if the large one is cold. If it is cold,, you have an issue with the temp door actuators that position the damper doors.
BC
Tech Contributor
Joined: Dec 1999
Posts: 32,910
Likes: 2,402
From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
This procedure is out of the service manual for your MANUAL Control HVAC System.. You have ONE controller rather than the two for the duel zone HVAC
Temperature Actuator Replacement
Removal Procedure
Remove the front floor kick-up panel. Refer to Kick-Up Panel Replacement - Front Floor in Interior Trim.
Remove the cover from the IP electrical center.
Remove the HVAC CON (HVAC controls) MiniFuse® #27 from the IP electrical center.
Remove the IP upper trim pad. Refer to Trim Pad Replacement - Instrument Panel (I/P) Upper in Instrument Panel, Gauges and Console.
Remove the instrument panel cluster (IPC) to steering column bracket retaining screws.
Reposition the IPC to better access the temperature valve actuator.
Remove the LH side window defogger outlet duct - lower.
Remove the push-in retainer.
Use a twisting motion to release the defogger outlet duct - lower from the windshield defroster duct, then from the defogger outlet duct - upper.
Disconnect the electrical connector from the temperature valve actuator.
Remove the temperature valve actuator retaining screws.
Remove the temperature valve actuator.
Installation Procedure
Position the temperature valve actuator, then align the slots in the temperature valve actuator driver to the flats on the temperature valve shaft.
Important
The actuator driver should completely seat onto the temperature valve shaft and the actuator mounting holes should be flush with the mounting bosses on the HVAC module case.
Slide the temperature valve actuator driver onto the shaft, while aligning the actuator locating hole to the forward alignment pin on the HVAC module case.
Notice
Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.
Install the temperature valve actuator retaining screws. Tighten
Tighten the temperature valve actuator retaining screws to 1.5 N·m (13 lb in).
Connect the electrical connector to the temperature valve actuator.
Install the LH side window defogger outlet duct - lower.
Use a twisting motion to secure the defogger outlet duct - lower to the defogger outlet duct - upper, then to the windshield defroster duct.
Install the push-in retainer.
Install the IPC into position.
Install the IPC to steering column bracket retaining screws. Tighten
Tighten the IPC to steering column bracket retaining screws to 3.5 N·m (31 lb in).
Install the IP upper trim pad. Refer to Trim Pad Replacement - Instrument Panel (I/P) Upper in Instrument Panel, Gauges and Console.
Install the HVAC CON (HVAC controls) MiniFuse® #27 to the IP electrical center.
Install the cover to the IP electrical center.
Install the front floor kick-up panel. Refer to Kick-Up Panel Replacement - Front Floor in Interior Trim.
--------------------------------------------------------------------------------
Document ID# 217995
1999 Chevrolet/Geo Corvette
Temperature Actuator Replacement
Removal Procedure
Remove the front floor kick-up panel. Refer to Kick-Up Panel Replacement - Front Floor in Interior Trim.
Remove the cover from the IP electrical center.
Remove the HVAC CON (HVAC controls) MiniFuse® #27 from the IP electrical center.
Remove the IP upper trim pad. Refer to Trim Pad Replacement - Instrument Panel (I/P) Upper in Instrument Panel, Gauges and Console.
Remove the instrument panel cluster (IPC) to steering column bracket retaining screws.
Reposition the IPC to better access the temperature valve actuator.
Remove the LH side window defogger outlet duct - lower.
Remove the push-in retainer.
Use a twisting motion to release the defogger outlet duct - lower from the windshield defroster duct, then from the defogger outlet duct - upper.
Disconnect the electrical connector from the temperature valve actuator.
Remove the temperature valve actuator retaining screws.
Remove the temperature valve actuator.
Installation Procedure
Position the temperature valve actuator, then align the slots in the temperature valve actuator driver to the flats on the temperature valve shaft.
Important
The actuator driver should completely seat onto the temperature valve shaft and the actuator mounting holes should be flush with the mounting bosses on the HVAC module case.
Slide the temperature valve actuator driver onto the shaft, while aligning the actuator locating hole to the forward alignment pin on the HVAC module case.
Notice
Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.
Install the temperature valve actuator retaining screws. Tighten
Tighten the temperature valve actuator retaining screws to 1.5 N·m (13 lb in).
Connect the electrical connector to the temperature valve actuator.
Install the LH side window defogger outlet duct - lower.
Use a twisting motion to secure the defogger outlet duct - lower to the defogger outlet duct - upper, then to the windshield defroster duct.
Install the push-in retainer.
Install the IPC into position.
Install the IPC to steering column bracket retaining screws. Tighten
Tighten the IPC to steering column bracket retaining screws to 3.5 N·m (31 lb in).
Install the IP upper trim pad. Refer to Trim Pad Replacement - Instrument Panel (I/P) Upper in Instrument Panel, Gauges and Console.
Install the HVAC CON (HVAC controls) MiniFuse® #27 to the IP electrical center.
Install the cover to the IP electrical center.
Install the front floor kick-up panel. Refer to Kick-Up Panel Replacement - Front Floor in Interior Trim.
--------------------------------------------------------------------------------
Document ID# 217995
1999 Chevrolet/Geo Corvette
Last edited by Bill Curlee; Nov 12, 2012 at 06:17 AM.