Originally Posted by 8VETTE7

Here is a list of ground locations and what is grounded at each location for the C5.


http://forums.corvetteforum.com/1548038331-post1.html

And the C5 and grounding does make complete sense if you take the time to understand what is actually happening.

Originally Posted by Bill Curlee

OK,, Ill throw my 2 cents in! Seeing how you have U DTCs, and there on the LDCM, RDCM & RFA,, I be willing to bet that you have a poor CONNECTION in one or BOTH of your DOOR WIRING HARNESSES CONNECTORS!

Here’s the deal. Pop the accordion tube out of both doors:





Once you get the accordion tubes popped out of the door and door frame, pull the wiring harness connectors out of the door frame A pillar hole. Once you have them out, un-plug the connectors and inspect ALL the pins (MALE & FEMALE) Look for damage, corrosion and deformation.

On this connector, (power plug) the female pin on the TOP ROW "center pin), is deformed. The little metal tong is bent down and will cause a poor intermittent connection. When the module gets power interruptions or spikes in power, it causes CAOS on the serial data line and the modules can NOT COMMUNICATE properly. It can and will cause the car to shut down.

Sounds simple enough but, this issues has stranded me more than once before we figured out what caused it. Sometimes just shaking the hell out of the accordion tube/wiring harnesses will be enough to get you back on the road!. I’ve even seen it fix its self when you close and open the door!

Just re-bend the little metal tong back in place and carefully reconnect the connectors (with the rubber accordion tube back on ) and see if that resolves that issue.




Having a low charge on your battery and or a weak battery can and will leave History U series DTCs. The U-series DTCs happen immediately during the crank session because your battery voltage drops LOW enough for some modules to shut down because of a B+ voltage below 9 VDC!
If your battery is low or needs to be replaced, get it recharged or replaced.

Originally Posted by Got uid0

Does this only occur at certain speeds?

Possibly speed sensor damage or unplugged on the wheel bearing?

Originally Posted by sunchaser73

Here's my $0.02 to go along with the other great advice: check your ignition fuses in the Instrument Panel Electrical Center. I had a similar problem to yours, and the source was a $3.30 fuse.

With your KEY ON, ENGINE OFF => wiggle each fuse back and forth and see if the power cuts in and out. Perhaps the female connections are loose.

Also...Bill Curlee's advice is worth TWICE its weight in gold...he helped me out with my issue...

Good luck!