PIT4600E

Bulletin No.: PIT4600E
Date: Nov-2012
Subject:
2-Mode (Hybrid) EBCM Programming And Set up
Models:
2009-2013 Cadillac Escalade Hybrid
2008-2013 Chevrolet Tahoe and GMC Yukon Hybrid
2009-2013 Chevrolet Silverado and GMC Sierra Hybrid
with Two-Mode Hybrid System (RPO HP2)
This PI was superseded to update model years. Please discard PIT4600D.
The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.
Condition/Concern
The following EBCM Relearn procedure is required anytime the EBCM is replaced or has been SPS reprogrammed. The Relearn is NOT required when the
Automated Brake Bleed procedure is performed because the EBCM Relearn is already being performed during the Automated Brake Bleed procedure
(Document ID: 2162047).
Recommendation/Instructions
Note: The vehicle must be at least 35 Degrees Fahrenheit (1.6 C) or warmer before performing the set up procedures below. Use a contact thermometer or
an infrared temp gun to measure the temperature of the EHCU. The relearn procedure should not be performed if the ECHU temp is below 35 degrees F (1.6
C). Access the module setup screen under the electronic brake control module (EBCM) screen of the Tech 2 scan tool.
1.
Perform the EBCM Relearn: The screen will have a soft key labeled "RESET". Press the soft key and the screen will read "test in progress" for 2
minutes before returning to the main screen.
2.
After 2 minutes has elapsed and the Tech 2 returns to the main screen, turn the key to the OFF position.
3.
Open the driver's door and wait 1 minute before starting the vehicle. This will disable the retained accessory power allowing the High Speed LAN bus to
go to sleep and write the data to the EE prom in the EBCM.
Note: The Acceleration Sensor Reset (Yaw/Lat Sensor) and the BMC Primary Piston Position Relearn that is listed under module setup will not need to be
performed because the two relearns are already being performed during the EBCM Relearn.
ADDITIONAL SI KEYWORDS:
2-mode ABS control DTC electrical mode program two two-mode
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.
GM bulletins are intended for use by professional technicians, NOT a "do-it-yourselfer". They are written to inform these technicians of conditions that may
occur on some vehicles, or to provide information that could assist in the proper service of a vehicle. Properly trained technicians have the equipment, tools,
safety instructions, and know-how to do a job properly and safely. If a condition is described, DO NOT assume that the bulletin applies to your vehicle, or that
your vehicle will have that condition. See your GM dealer for information on whether your vehicle may benefit from the information.
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