Lucerne V8-4.6L (2008)
Wiring Harness: Customer Interest
Electrical - MIL ON/Multiple DTC's Set/Hard Or No Start
TECHNICAL
Bulletin No.: 06-06-04-021B
Date: October 09, 2009
Subject: Malfunction Indicator Lamp (MIL) - Check Engine Light On, No Start, No Crank, Loss of Backlighting on PRNDL Display, and/or DTCs
P2761, P0712, P0713, P0716, P0717, and/or P0748 Set (Repair and Re-Route Transmission Wiring Harnesses)
Models:
2006-2009 Buick Lucerne
Supercede:
This bulletin is being revised to update the Correction information. Please discard Corporate Bulletin Number 06-06-04-021A (Section 06 - Engine).
Condition
Customers may comment on a no start, no crank, an Illuminated check engine light, or the loss of backlighting on the PRNDL display.
A technician may find DTCs P2761, P0712, P0713, P0716, P0717 and/or P0748 set.
Cause
The transmission wiring harness may be misrouted and pulled tight against the transmission shift cable bracket or transmission case. This condition may
cause wire damage or a poor connection at the transmission connector.
Correction
1. Inspect the transmission wiring harness for contact against the shift cable bracket or transmission case. If wiring harness contact is found, proceed
to Step 4.
2. Inspect the transmission wiring harness for excessive tension on the transmission connector. The transmission connector may be loose. If wire
harness tension is found, proceed to Step 3.
3. Trace the transmission wiring harness back from the transmission connector toward the bulkhead. Just forward of the braided brake lines, the
transmission wiring harness breakout is taped to the main engine wiring harness in a horse shoe shape. Cut the tape back in this area to release the
tension on the harness. Proceed to Step 6.
4. Repair the portion of the wire harness that is damaged. If present, use a hand file to remove any sharp burrs on the shift cable bracket.
5. Re-route the transmission wiring harness away from the shift cable bracket or transmission case.
6. Test the vehicle to ensure that no DTCs are set or that the MIL lamp or PRNDL display backlight is on.
