PIT5206B

- 2014,2013,2012,2015 - crc - 5/6/14
Black plate (1,1)
File in Section:
Service Bulletin
-
Bulletin No.:
PIT5206B
Date:
May, 2014
PRELIMINARY INFORMATION
Subject:
Unwanted Grade Braking - Low Power - And/Or Transmission Busy Shifting
Models:
2012-2015 Cadillac Escalade Models
2012-2013 Chevrolet Avalanche
2012-2015 Chevrolet Silverado, Suburban, Tahoe
2012-2015 GMC Sierra, Yukon Model
This PI was superseded to update model list. Please discard PIT5206A.
The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.
Condition/Concern
Some owners may comment of any/all of the following issues:
– Unwanted grade braking when not going down a grade
– Reduced/Low engine power with no DIC messages or DTCs (Brake Pedal Override Feature)
– Transmission busy or frequent up and down shifts with no DTCs
These issues may be caused by the Brake Pedal Position (BPP) sensor not being learned correctly in the ECM
(Engine Control Module).
Recommendation/Instructions
To view the BPP data in the ECM use the scan tool and build it as follows:
Tech 2 (2013 and older models): Powertrain/ Select Engine Type/ Engine Control Module/ Data Display/ Auto
Transmission Data
GDS (2014 and newer 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 (+/- .3 volt approximately) with pedal released)
BPP Sensor Learned Released Position = Voltage (should equal the BPP sensor voltage with pedal released)
Note: NOT ALL ENGINE TYPES WILL HAVE ALL OF THE ABOVE PARAMETERS.
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. When looking
up the ECM BPP relearn procedure in SI, there will be a relearn procedure for the BCM and one for the ECM. Make
sure you are using the ECM relearn procedure, example SI Doc ID's: 2655204 (old body style) and 2535744 (new
body style).
Diagnostic Tip for old body style: If the ECM will not perform a BPP Sensor relearn, then SPS program the
ECM. After the ECM SPS programming is complete, the BPP will relearn. Use the scan tool to verify the BPP
Sensor is now showing 0% with the brake pedal released.
- 2014,2013,2012,2015 - crc - 5/6/14
Black plate (2,1)
Warranty Information
For vehicles repaired under warranty use:
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.