ground problem? or something else?

[Rob99]

The issue is on my 04' 6sp coupe, i noticed is;
No cruise, brakelights, tails, or rear side marker lights, when i depress the brake pedal the IP lights come on and the chime starts ( like when you have the key in).
What iv tried from reading around a bit is to change out the 2 stoplight switches under the dash, nothing changed after that, so am i looking at a grounding issue?

Also the front park lights work, the 4 way hazards work i have Euro tailights and when i briefly connected the cut white wire i had lights back there although not the correct orientation (thats why cutting the white wire is needed with the Euro install ( iv had these for years with no prob's)
Anyone have an idea what could be the prob? TIA Rob99

Here's another interesting gremlin when locking with the fob it sets off the alarm

[gmjunkie]

The first thing I'd do is pull the codes and wright them down and post them. Both History and Current!

How to Pull Codes: C5
1. Turn your key to the "ON" position, but do not start the engine.
2. Clear any present messages by pressing the RESET button.
3. Hold the OPTIONS button down, and press the FUEL button 4 times. (This will get you into the "codes" section of the DIC.
4. The computer will automatically display all the codes your car has created. It will cycle through each code every 3 seconds. (Have a pen and paper handy to write down the codes)

Note: Any code that ends in an "H" is a history code (something that has occurred in the past, but is not reporting as an error currently.)

5. Once the computer has finished going through all of its codes, press RESET to enter Manual Configuration mode. It should start with a module and show "NO CODES" or "# Codes."
6. To optionally reset codes once in manual mode, press and hold RESET until is displays "NO CODES."
7. Press OPTIONS to go into the next module (ie, from PCM, or Powertrain Control Module, to TCS, or Traction Control System.)
8. Repeat Step 6 until you have reset all the codes in all the computer modules.

Note: Only reset the codes if you want to- it is not necessary to reset them every time you pull the codes.

9. When finished, simply take your key out of the ignition.


It definitely sounds like you have a ground Feedback problem,So I would Clean and Inspect All Chassis Grounds and go from there!~!!


PS Grounding points 1,4 and 5 are under interior trim panels.

[Rob99]

Hey gmjunkie thanks for the reply& suggestions, today i checked the grounds #3 at the rear there was no #2 just a stud, #'s 6,7,8 in front, i found #9 a little tricky cause it's under the plastic battery surround i wasn't able to get it off cause it got dark and cold but it looks like it may have some rust/corrision on it, the others mentioned above seemed to be ok although i cleaned and coated them anyway.
Also #7,8 up front, besides being on studs which i cleaned and coated have a plug associated with them i tried to pull it apart with no success, if i don't solve the problem with the stud ground mounts I'll have to go back to them(althouigh i did spray the ZeP penetrant & moisture displacer right into the back of the plug where you can see the connectors).
So far nothing has changed, i even disc the batt for a while to see if that would do anything, i also checked the codes with my Innova scan tool all i got was P 1154 & 1134 which iv had before (o2sensors) and on the DIC; TCS 1276H.

Would you know where i can find a reference as to what each ground point is responsible for?
Thanks again for the help.

[Rob99]

DSCF0071.jpgDSCF0072.jpg

After checking the last ground on the frame by the battery with still no lights i went back to the tails and removed them all to see if there was somthing loose there, i also check the weather pak connection by the pass rear wheel well area thats where the tailight loom connects and this is what i found as soon as i saw the melted wire loom from contacting the muffler i knew i had solved the problem only to my surprise the 3 wires inside didn't have any damage so i was confused, luckly i have an extra set of Euro lenses and wire set that i swaped out and the lights are working properly DSCF0073.jpg

[Hib Halverson]

(big snip)
Would you know where i can find a reference as to what each ground point is responsible for?
Thanks again for the help.

The factory service manual contains that information both in wiring diagrams and, in some cases, component locators. You can buy FSMs from Zip Products. They stock a lot of them and have pretty good service. I get my manuals from them.