Weird electrical/light issues

cochrank

Well-known member
Joined
Nov 23, 2005
Location
Erie, PA
TDI
2002 Jetta
Group, I am back again trying to find help. I just recently purchased another TDI Jetta (2005.5) MkV. Going through some things and fixing the issues that the previous owner had and I am running into some lights issue. see VAGCOM for electrical.

5 Faults Found:
00987 - Lamp for Brake Light; Left (M9)012 - Electrical Fault in Circuit 00988 - Lamp for Brake Light; Right (M10)012 - Electrical Fault in Circuit 00985 - Right Tail Light (M2)012 - Electrical Fault in Circuit
01504 - Bulb for License-Plate Light (X)012 - Electrical Fault in Circuit
01117 - Generator Terminal DF Load Signal 008 - Implausible Signal

The bulbs are good and I have checked all the fuses. Reverse lights work, headlights, marker etc. Just these lights. Anybody have any suggestions?
 

cochrank

Well-known member
Joined
Nov 23, 2005
Location
Erie, PA
TDI
2002 Jetta
I should add I also cleaned all grounds under the air box thinking it might be a ground issue. Previous owner did something to it (maybe jumped started in reverse) that blew out the 200 amp fuse in engine compartment. Unsure if this is related
 

relumalutan

Veteran Member
Joined
Dec 6, 2012
Location
Michigan
TDI
06 Jetta TDI Special Edition
Google search works all the time:
https://www.youtube.com/watch?v=rl6LD3pcMuM

https://www.ebay.com/itm/CECM-Centr...970628&hash=item4201e1b0eb:g:BicAAOSwA1Nc7Yka


Also, keep in mind: even if all the bulbs look Ok, they still might be the cause of at least some of the errors. Over time, the filament in the bulb gets worn out. When the key is turned in ignitions the CANBUS module performs what is called the cold diagnostics (it sends a quick electric charge to all the bulbs to see if any are burned). Due to the worn out but not yet completely failed filament the CANBUS might register an error. Perhaps installing new bulbs will save you time and $ involved with the removal and replacement of the CECM module.
 
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cochrank

Well-known member
Joined
Nov 23, 2005
Location
Erie, PA
TDI
2002 Jetta
I saw this online as well but I was wondering how do you test to see if this is bad or just a potential chaffed wire. Is there an easy way besides performing continuity on each wire?
 

Texas_sky

Veteran Member
Joined
Dec 23, 2007
Location
ATX/Mile Hi
TDI
2001 GOLF TDI 2dr 5spd
My odometer display (06 jetta) is always intermittently working sometimes it goes blank and sometimes it's distorted and sometimes it works. I heard if you replace a bad door lock actuator it will clear up the problem. I also have a slight one second delay sometimes when starting the car before it fires. Anyone experienced this?
 

cochrank

Well-known member
Joined
Nov 23, 2005
Location
Erie, PA
TDI
2002 Jetta
Group,

Well I am getting closer. I have the tail lights fixed. It was just as relumalutan stated. The bulbs looked good but there must have been a slight break because I changed bulbs and they work. However the license plate lights do not work. I do not have power to them. I tested continuity all the way where it goes into the rear fender and it is solid there (read some posts where the trunk hinge wires busted due to use). I don't know where these wires go after that to check for continuity. I also checked the door harnesses for breaks and nothing.

Unsure if this is related but my radio is screwy as well. I had to replace the original with a working model but I do not get any reception (barley any staticy noise coming from the speakers) and there is a loud crackly noise from the top front speaker in the door (blown??) again unsure if these are related but I wanted to mention it.

Would the Control module impact the radio as well?
 

cochrank

Well-known member
Joined
Nov 23, 2005
Location
Erie, PA
TDI
2002 Jetta
Group,

I wanted to give and update. I have figured out my light issue. It was stumping me why I didn't have power. I looked at everything (wires, fuse, etc.) but no power. By happenstance I was testing the power when it was initially started and bingo, I had 12V. It lasted for ~ 5 sec before there was no power. So I realized that the system was doing the cold test and since there was no feedback killed the power. With that in mind I then tested continuity of the light terminals, they were fine but had to do a little digging. They didn't look bad but I cleaned them anyways and put on dielectric grease. The bigger issue was the light socket itself. One was pitted so it was not making great connection. The others were oxidized just enough not to make a good connection. Cleaned and greased and now they work. Hope this helps someone else. Little bit of oxidation has a big impact.
 
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