Owners of 2012-2014 Cadillac Escalades may complain of unwanted grade braking when not going down a grade, reduced engine power with no DIC messages (or DTCs) and transmission busy/frequent up-down shifts.
These issues may be caused by the brake pedal position (BPP) sensor not being learned correctly in the ECM.
To view the BPP data in the ECM, use the Tech 2 scan tool: Powertrain/Select Engine Type/Engine Control Module/Data Display/Auto Transmission Data GDS (2014 models); Module Diagnostics/Engine Control Module/Data Display/Automatic Transmission Data.
Scroll down and view the following parameter:
BPP Signal = Applied or Released (should read Released with brake pedal released).
BPP Sensor = 0% to 100% (should read 0% with brake pedal released).
BPP Sensor = Varying Voltage (should read near 1 volt (+/- 0.3 volt) with pedal released.
BPP Sensor Learned Released Position = Voltage (should equal the BPP sensor voltage with pedal released).
With the brake pedal released, use the BPP sensor parameters to determine if the ECM has learned the BPP released position correctly. If the BPP sensor learned released position voltage does not match the BPP sensor voltage with the pedal in the released position, the ECM will need to have a BPP relearn performed.
If the ECM will not perform a BPP sensor relearn, use the Tech 2 to verify that the BPP sensor is now showing 0% with the brake pedal released.
Sign up for a FREE subscription to Auto Service Professional magazineSubscribe