Brakes - Difficult Pedal Application/Pedal Buzzes
TECHNICALBulletin No.: 08-05-22-001A
Date: October 28, 2008
Subject:
Pedal Noise/Buzz, Extra Effort Needed to Depress Brake Pedal After Vehicle Has Not Been Driven for Extended Period of Time (Reprogram Electronic Brake Control Module (EBCM))
Models:
2008 Chevrolet HHR SS
Built Prior to and Including VIN Breakpoint 8S653008
Supercede:
This bulletin is being revised to provide a VIN breakpoint. Please discard Corporate Bulletin Number 08-05-22-001 (Section 05 - Brakes).
Condition
Some customers may comment that after their vehicle has not been operated for an extended period of time, there may be a noise or buzz coming from the brake pedal or extra effort may be needed to depress the brake pedal.
Correction
Important:
The following Optimized Hydraulic Brake (OHB) characteristics are considered to be normal and no mechanical parts should be replaced in an effort to change the operation of the system:
^ Ratchet sound coming from the brake system during OHB activation.
^ Brake pedal movement or pulsation when the OHB is active.
^ Increased brake pedal effort under low brake booster vacuum.
^ Change in brake pedal effort when OHB is active.
^ Frequent brake stops may result in OHB activation.
^ High altitude driving may result in OHB activation.
Refer to Corporate Bulletin Number 07-05-22-002 for further information on Optimized Hydraulic Boost Brake System Characteristics.
DO NOT replace the brake vacuum booster, brake vacuum sensor, EBCM or ABS module for this condition.
An Electronic Brake Control Module (EBCM) calibration was released that may reduce the effort the customer feels when depressing the brake pedal on a car that has not been operated for an extended period of time. Reprogram the EBCM with updated calibration files using the TIS2WEB Service Programming System (SPS) application. As always, make sure your Tech 2(R) is updated with the latest software version.
Warranty Information
For vehicles repaired under warranty, use the table.
Disclaimer