Lifty Not Nifty
This bulletin applies to 2007-2014 Cadillac Escalade and Escalade ESV vehicles. Some customers may state that the power liftgate is inoperative from all the switches and the keyless entry transmitter only with the ignition in the off position. If the ignition is in the accessory or the run position, the liftgate will operate correctly.
If you experience this concern, check for power on the “accessory wake up data line” going to the ECM and the TCM. With the key in the accessory position, check for battery voltage on circuit 5985 going to pin 18 (2007 and 2010 to 2014 model years) or pin 31 (model year 2008 to 2009) of connector 1 of the ECM and pin 11 (LT1 transmission) or pin 9 (for MYC transmission) to the TCM.
If no voltage is present with the key in the accessory position, check for a wiring or pin fit concern.