Wonder if someone can give me their thoughts.
Air bag light on. Turn ignition on light flashes 7 times and then stays on.
Connect diagnostic unit to car. "CAN NOT CONNECT" comes up on scanner.
Tried a new SNAP ON diagnostic tool and same result . Will not connect to air bag module. Had a look at manual and wiring diagrams. 1998 C5 has a simple system where it is stand alone and not connected to body control module. Just module and sensors. Stand alone system.
Checked power and ground at air bag module plug, both o/k.
Checked continuity from Module Plug to Diagnostic Port and this is also okay.
I had passenger seat out of the car and thought maybe this would cause a problem but wiring diagram shows no inter connection.
Having a look at the factory manual it pointed to Air Bag Module.
SO I Bit the bullet and purchased brand new Air Bag Module through vendor on the forum.
Light still on and message on scanner is still can't / won't connect to module.
Am I missing something. Any advice would be much appreciated.
I have checked all connections to air bags and sensors.
Even with a new Air Bag Module two different diagnostic tools will not or can't connect?
Both Scanners will let me into all other areas.

 

Did you also check that you have Ignition 1 voltage at pin 10?

 

Please read and post your DTCs. That will narrow down the issue.

READING YOUR Engine Diagnostic Codes



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 OPTIONS
4) While holding OPTIONS, press FUEL four times within a 10-second period.


Initially, on-board diagnostics go into an Automatic Mode which 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. ( 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 kinds of diagnostic codes, Current and History designated with a letter suffix, “C” or “H”. A current C code indicates a malfunction is present and active 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 English/Metric (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 and hold the RESET button 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.
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. You can GOOGLE the DTC and also find information on it.




Here is very good site that explains the DTCs:


http://www.corvette-web-central.com/C5DTCcode.html


http://www.obd-codes.com/trouble_cod...d-ii-codes.php



Make sure to include the H or C suffix!!

 

with both above. Pull codes first. Then check for 12 volts and ground to the module.

 

Thanks for your replies. I have checked voltage, ground, circuit continuity etc.
Have also pulled codes. Checked service manual for diagnostic procedures and all pointed to Air Bag Module. Well I will just keep going. Secret is just keep working systematically and keep emotion out of it.(This can be difficult!!)

 

And what were the results? Codes? Voltage? Resistance to ground?

 

OKAY!!!FOUND THE PROBLEM.
The problem was a faulty clock spring. Clock spring was broken.
I was using later model scan tools which would not let me in to the air bag module. I was able to access all other areas of the car. The early model C5's had a stand alone air bag system which is reasonably basic.

Grounds were tested. There was some resistance and this was fixed.
Power supply was okay and there was no voltage drop.
Diagnostic wire from air bag module to scan socket was okay and this also had a signal when checked with osciliscope. This showed that the module was sending out info but the scan tool would not read it.

The conclusion was that the later model scan tools were not reading the signal from the early model air bag system.

I located an EARLY tech 2 scan tool which enabled us into the air bag module and consequently indicated the clock spring was the problem.

Of course I had already purchased a new air bag module and tried it. I figured since the scan tools I had used would read everything but the air bag system the problem was in the module.
Thanks for your input guys. Being in Australia there is not much knowledge or information available. c5's and c6's are extremely rare and very expensive over here.(later model Vettes must be converted to right hand drive over here a 40k + excercise). The conversion costs more than the car.

 

Can you tell me what year that early model tech 2 scan tool was. I'm have a problem with my scanner not connecting to air bag module after replacing a complete deployed system with used parts. Air bag light on steady.

 

Ed

What DTCs are you see for the air bad system?? Use the C5 DIC Internal Scanner and report those DTCs

BC

 

Problem solved. I found out the 97 to 99 C5 DIC or newer scanners won't connect to SIR have to use tech 2 scanner. located one and fix my air bag light.

 

where did you locate Tech 2 scanner and how much?