Wiring Harness 2016 FPIU

[dwu048]

Hi all. I recently bought a 2016 FPIU. The tailgate has not been fully functioning and I have the wrench light on for a BCM and RCM DTC - the BCM producing the wrench DTC on the dash. I was trying to trace the wires from the tailgate to the front and discovered the wire loom was all pinched. Is this an easy fix? How would one go fixing these wires instead of paying $1500 for a new wiring harness? I hope that I will be able to fix the tailgate and the DTC for the BCM and RCM. These wires are located by the side of the parking brake.

 

[mmorey79]

If all of the wires have a few inches from the connector that are in tact, and the pictured area is the extent of the damage, I'd just splice them one at a time and make sure they're taped/insulated well. You won't have any issues as long as your splices are good, wire size is correct, and in the case of twisted pairs of CANBUS wiring, that you make your replacement similarly twisted (it's not critical that it's perfect, but over the entire length of the car the twist helps prevent electrical noise from causing issues). If you have any that are damaged at the connector you'll need to depin them and get replacement pins/pigtails of wire. If you're not comfortable doing the work most bigger cities have one or more "auto electrical" specialist shops that would probably be best suited to make that repair.

 

[dwu048]

If all of the wires have a few inches from the connector that are in tact, and the pictured area is the extent of the damage, I'd just splice them one at a time and make sure they're taped/insulated well. You won't have any issues as long as your splices are good, wire size is correct, and in the case of twisted pairs of CANBUS wiring, that you make your replacement similarly twisted (it's not critical that it's perfect, but over the entire length of the car the twist helps prevent electrical noise from causing issues). If you have any that are damaged at the connector you'll need to depin them and get replacement pins/pigtails of wire. If you're not comfortable doing the work most bigger cities have one or more "auto electrical" specialist shops that would probably be best suited to make that repair.

Thank you for the reply. The wires seem okay—just a good measure to cover them up with tape. I believe the issue is further up toward the smart junction box. Somewhere along the line, the wire is pinched somewhere else.

 

[peterk9]

Thank you for the reply. The wires seem okay—just a good measure to cover them up with tape. I believe the issue is further up toward the smart junction box. Somewhere along the line, the wire is pinched somewhere else.

What exactly is meant by the liftgate is "not fully functional"?

Peter

 

[dwu048]

Toggle the switch in the overhead, run to the back, and press the latch switch, the door still does not open. I've tested the switch and the actuator on the bench and both are working with 12V.

 

[peterk9]

BY actuator are you referring to the liftgate motor strut or the lock actuator? Do you hear anything regarding an attempt by liftgate to unlock and/or open? If you meant the motor strut, did you check to see if it was getting power from the connector? What DTC code (s) are you getting?

Peter

 

[dwu048]

BY actuator are you referring to the liftgate motor strut or the lock actuator? Do you hear anything regarding an attempt by liftgate to unlock and/or open? If you meant the motor strut, did you check to see if it was getting power from the connector? What DTC code (s) are you getting?

Peter

===BdyCM DTC B12E8:11-48===
Code: B12E8 - Liftgate/Tailgate Control/Release Switch

Additional Fault Symptom 11):
- Circuit Short To Ground

Status (-48):
- Previously Set DTC - Not Present at Time of Request
- Malfunction Indicator Lamp is Off for this DTC
- Test not complete

Module: Body Control Module

===END BdyCM DTC B12E8:11-48===

===BdyCM DTC B11D8:01-8A===
Code: B11D8 - Restraint Event Notification

Additional Fault Symptom 01):
- General Electrical Failure

Status (-8A):
- DTC Present at Time of Request
- Malfunction Indicator Lamp is On for this DTC

Module: Body Control Module

===END BdyCM DTC B11D8:01-8A===

===BdyCM DTC B12EE:15-08===
Code: B12EE - Liftgate/Tailgate/Trunk Release

Additional Fault Symptom 15):
- Circuit Short To Battery Or Open

Status (-08):
- Previously Set DTC - Not Present at Time of Request
- Malfunction Indicator Lamp is Off for this DTC

Module: Body Control Module

===END BdyCM DTC B12EE:15-08===

===BdyCM DTC B12F4:14-0A===
Code: B12F4 - Vehicle Speed Output

Additional Fault Symptom 14):
- Circuit Short To Ground Or Open

Status (-0A):
- DTC Present at Time of Request
- Malfunction Indicator Lamp is Off for this DTC

Module: Body Control Module

===END BdyCM DTC B12F4:14-0A===

I feel like they are all tied together. Just can't figure out where in the loom it is damaged. I do suspect it is near the steering wheel column as it was a mess in there. The previous owner even had the ignition wire spliced and connected to the fuse directly bypassing the severed wire.

 

[peterk9]

Based on your post and my limited knowledge, it does appear to be an electrical/wiring issue rather than a mechanical one. This will likely require patience and time to repair. Good luck.

Peter