I'm in need of y'alls help. Please bear with me as I explain. I have a 99 vert. 82k miles. I've owned it for 1.5 years with no issues. Earlier last month I drove to Mississippi and back to SC with problems at all. Well, today I took the car to my mechanic for an oil change. After I left to go pick my daughter up from kindergarten. It is about a mile from the shop. While waiting in line the DIC started flashing service traction control, service active handling,service tire pressure ( I do have two bad TPMS), service vehicle, security light was on. I went straight back to mechanic to show him. He plugged in his Tech 2 and got codes representing g the warnings. I had to leave to pick up my other daughter from high school and take the car back home for the SUV. He advised me to take the car home. At home I pulled the codes myself . It showed 1 IPC for Serial Data Line Malfunction. 1 PCM code for Theft Deterrent and 4 RFA codes for Loss Communication with IPC, PCM, and 2 TPMS which were already there.
I then drove the car ten miles, cleared all codes, and drove ten miles back home. As I pulled I my garage the DIC lit up and went crazy!!! War I vs for reduced power, traction control, active handling, tire pressure, service vehicle, and the radio and HVAC went dead for a few secs. I backed under garage and pulled the codes. CRAP! 31 codes !! Even though most of the codes were repeats in different modules there were some new ones. Class Two Circuit Shorted to Battery, and Serial DAta Line Malfunction were in addition to many Loss of Communications to PCM. BCM, IPC, TCS, RFA.

Does anyone know what the he k is going on? FYI my bezel has been removed and sent to Dennis at DD. It's been this way for over a month with no issues until today. Any advise is appreciated.

Sorry for long text. I accidentally hit submit earlier before I finished and got delayed.

 

Did you do a search? These codes are common.

 

It almost sounds as you have a loose battery cable or ground. Was that checked? That's a lot of different systems to go crazy at the same time, symptomatic of a voltage issue...but the true gurus will speak shortly.

edit..

.I can see in your other post on same subject, Guru 8vette7 has chimed in...trust his help.

 

Check this thread and see if this helps.
https://www.corvetteforum.com/forums...-there-is.html

If you don't feel comfortable doing the things in the link, show it to your mechanic. GL and keep us informed.

 

Update...I went to my mechanic and advised him of the 31 codes. He and another mechanic who also had experiience.on c5's asked me to try unplugging the wire harness under the drivers seat ( the harness with the two purple wires in it) . He said this controlled the seat memory and steering column. He said he had seen this same type of crazy warning codes come from a shorted wire in that harness and it caused all the modules to look as if they were going bad and losing communication. Couldn't hurt to try. So this evening after work, I cleared the codes (with engine off) unplugged wire harness , and drove around a few miles, went home and parked under garage. With engine still running I checked the codes and only showed the code for driver over west memory and steering column ( and the two TPMS which I knew were bad).
My question is do you guys think that fixed it or do I need to go a long ways. I wasn't sure if it would read the error/code immediately or take some time.
Have y'all heard of this as a fix ?
Thanks

 

Probably was at least one of the sources of your problems. It could have a shorted wire or it could have bad connections in the pins where the harness connects to the seat. Not sure what the "driver over west memory" code is. That's a new one to me. When you re-connect the harness, do all the problems re-appear? If so, this would prove that its the culprit.

 

Auto spell correct on an iPhone is terrible to me....I think it was drive side seat memory. I did not reconnect it yet as I was t sure if I needed to run it for a longer period of time. I'll also check the pins....thanks for the heads up. I'll hopefully get to troubleshoot a little more tomorrow and will keep you posted.

 

I would drive it for a while and then see.

 

OK gurus, please chime in and offer more advice. Everything is dry under the seat and BCM. Connections looks good and battery cables are tight. After I crank the car no codes show for a while then all of a sudden all those warnings reappear. The car still runs. I can turn it off, recrank and DIC is clear for a while, then they rear their ugly head. Disconnecting seat memory harness under driver seat did not help. I'm open to suggestions and questions.

 

Thanks

 

Followed instructions on the provided link in earlier post. Problems seem to have been fixed; turns out it was the connector wire harness in driver door jam. The main power pin was loose causing all the intermittent loss of power to the other modules and creating false codes. Had the pins tightened and have driven about 100 miles with no issues. Pulled codes this afternoon and had none!!! Thanks for everyone's advice and help. You guys are awesome!😂👍