It looks like the entire driver's rear (LH) taillight is trying to find ground through the rear fog.

It also looks like that can throw an intermittent DSC fault.

My best guess is that I'm simply looking at a weak ground connection to the taillight housing on that side, bu I'm stumped by the DSC, because although it will indicate a fault, there are no active or pending codes.

Is there a big single ground point at the left hand rear of the car somewhere that I need to look at?

And for those that have had this problem, does the plug or socket side of the power connector fail?

 

Wa3ra,

Both rear tail light assemblies use the same, single grounding point located on the drivers side trunk area. It also looks like the grounds from each component come into a common harness splice before the grounding point which may warrant a look.

Up to 2005 Grounding Point (G1AR) - Harness Splice (CAS9) - Located Drivers side rear trunk

2005 - 2008 Grounding Point (G2AR)- Harness Splice (CAS61) - Located Drivers side rear trunk - Note Same Place as 2001-2005 G1AR, just numbering change.

See attached.

Click once to open and again to zoom



I have never experienced this - Interested about the DTC you are seeing....

 

wa3ra, silly question, did you just recently put in new bulbs into the tail light? You may have a bulb that is not seated quite right and that is causing your grounding issue. I would first start with pulling the base plate off of the rear tail light and just laying it inside the trunk. You can then remove all the bulbs and see what is happening (should cause things to act normally. You can then install your fog light bulb. From there, start installing the bulbs one at a time and see what happens. If things go south on you, then you can start looking at things. I would also take a look at the plug for the tail light and see if the pins are in good condition. If my memory serves me correct, there has been issues in the past where the ground pin has developed some corrosion on it and it has caused the tail lights to do funny things.

 

The bulbs were all changed about six months ago. It is odd that the driver's side is the troublemaker.

I did track down what was throwing the DSC fault; the reverse light on that side was falsing the LR wheel sensor, so it is definitely a ground issue. I've got to bundle up and go pull the taillight housing now, unless I wait for the car to come back from the body shop. The pass side rocker went the way of the driver's side, so we're cutting it all back and replacing it, and we're going to box out the lift points while we're at it.

On the driver's side, we had some help with the metal...this side is all on my dime.

 

Kudos to PanamaJag for the diagram.

CA137-6 is cooked in the connector, and the lead within the housing is toasty. I have this nasty habit of running with the rear fogs on, and apparently, the connection wasn't happy with that. That wiring is seriously underrated for full current!

It is a 2002, so I think I'll switch to LEDs to drop the consumption, then try running a new independent ground to the housing. If that doesn't do it, I guess I'll need to scavenge up a new connector and inner housing.

I just wish it were warmer than the 9ºF (-13ºC) that we had this morning!

 

Lancaster wasn't much warmer, can't work on the car without heated garage! my lover still lay cold in the garage, miss to take her for ride so bad!