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My drivers side DCU is not getting power. I checked fuse 39 and pin 8 of connector 3I on the rear SAM already. Both points in the rear have good voltage. Tried using ground in engine bay and power connector on DCU, still no good. Somewhere the positive wire is shorted to ground.
To add... f39, 3I rear SAM connection/pin 8, see attachments.
That's what I checked first using the ground point in the trunk. It shows good voltage from the fuse and the output pin into the harness. I also am having issue with the left headlight and marker light, so i'm hoping once I start tracing those faults I'll find the common point of failure.
That's what I checked first using the ground point in the trunk. It shows good voltage from the fuse and the output pin into the harness.
I also am having issue with the left headlight and marker light, so i'm hoping once I start tracing those faults I'll find the common point of failure.
Recap:
The +12 feed test ok at the SAM
No blown fuse
Also bad: left HL + Marker light !!
> You not getting a blown fuse makes me believe the feed line is not shorted. If it was shorted, an open fuse would be witness...
> The [Left Headlight + Left Marker + Left DCU] do not share power feed... very likely they share GND path to a painted post under driver side carpet. Disconnect batteries and clean GND!
(HL Power grounds nearby but logic GND likely at footwell)
Pull lining to check harness/connectors you can also check harness passing through tubing (5).
Can you share more relating to the pass-through cable? I've found that is the issue, but the cable you show seems to be the one inside the door, not the one that passes through the boot in the door hinge. That is where my problem is for the door. It seems the headlight issue is unrelated.
This is the cable I need to replace. It has a Yellow, Blue, and White connector on one end and goes under the floorboard carpet. I can't get any info on the part number for it.
Routes into main body harness as shown in post 7 see attached bulletin concerning replacement. If associated connectors inclusive of pins @ DCU & rear SAM are fine only DIY choice is to trace through body harness but before doing so check CAN voltage distributors.
Last edited by konigstiger; Mar 22, 2023 at 01:23 PM.
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