No Start No Crank Concern - keywords back fuse ISRVM lamp light mirror rear reverse starter wire

The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.

No start, no crank concern with no DTCs. This could be caused by an open BACKUP fuse in the UBEC. When the BACKUP fuse is open the P/N switch doesn't send a signal to the PCM that says it's okay to ground the starter relay.

1. Check for an open BACKUP fuse in the UBEC.
2. If the fuse is open check for a short to ground in the following circuits:

•	Circuit 239 Pink wire from the UBEC to the Park/Neutral switch pins 1 and 4.

•	Circuit 1786 Orange/Black wire from the Park/Neutral switch to the PCM.

•	Circuit 24 Light Green wire from the Park/Neutral switch to the back up lamps and the inside rearview mirror with RPO DF5.

Reference Document ID # for the wiring schematics

2005 Equinox 1386551 and 1369929

2006 Equinox and Torrent 1655370 and 1655421

Please follow this diagnostic or repair process thoroughly and complete each step. If the condition exhibited is resolved without completing every step, the remaining steps do not need to be performed.