Greetings all! I have a '94 Z-28, 6-speed, 140K. After much hair pulling trying to get the computer to talk to me, I finally tore the dash apart only to find that someone had removed the bulb to theservice engine soon indicator. I replaced the bulb and sure enough as soon as the car warmed up, the service engine light came on. I went to pull the codes, the light flashed for a split-second and went out, and didn't come back on. The fans came on so I know I'm in diagnostic mode, but, the computer won't talk to me. I need info on the diagnostic circuit so I can test it. Any help would be GREATLY appreciated!!

 

Can't flash codes on 94 and newer GM cars, you need a scanner. The 94 Camaros are OBDI and need a OBDI scanner. Some 94 cars that were built towards the end of the model run have OBDII diagnostic connectors, and in this case you will need a OBDI scanner and an adapter cord, OBDI scanner to OBDII connector. Look for details in computer section.

 

Another thing, some Chevy (and other GM) models get the OBDII power from the same circuit as the cigarette lighter/power socket. If a scanner ever has a problem communicating with the system, a blown fuse should be the first thing to check for. I don't know if the same is true for OBDI, but it's worth a look.

 

Thanks guys! I checked out the computer section as you suggested, found all the answers I was looking for. I'll find someone that can scan the codes for me. Thanks again!!