Sierra 2500 4WD V8-6.6L DSL Turbo (2007)
Electronic Noise Suppressor: Customer Interest
Audio System - AM Band Radio Noise
TECHNICAL
Bulletin No.: 08-08-44-006A
Date: October 07, 2008
Subject:
AM Band Noise, Radio Noise (Install Resistor)
Models:
2006-2007 Chevrolet Silverado Classic
2007-2009 Chevrolet Silverado
2006-2007 GMC Sierra Classic
2007-2009 GMC Sierra
with 6.6L Duramax(TM) Diesel Engine (VINs D, 2, 6 - RPOs LBZ, LLY, LMM) and RWD Allison(R) Transmission LCT1000 (RPO MW7)
Supercede:
This bulletin is being revised to add the 20062007 and 2009 model years. Please discard Corporate Bulletin Number 08-08-44-006 (Section 08 - Body
and Accessories).
Condition
Some customers may comment on AM band noise occurring while driving. It is acutely apparent when listening to the AM radio and driving under a
viaduct on the highway.
Cause
This noise may be generated by the engine control module (ECM) timing signal. This signal then radiates into the AM band, causing interference.
Correction
Technicians are to add a 330 ohm resistor in series with the 1827 circuit, pin X2-54 (yellow/black) on the engine control module (ECM) side.
1.
Locate ECM connector X2 (the bottom connector) under the hood.
2.
Locate pin # 54. Refer to Connector End Views in SI for the ECM X2. The wire is yellow/black in color.
3.
Cut the wire about 178 mm (7 in) away from the connector.
4.
Slide about 76 mm (3 in) of heat shrink tube on one end.
5.
Solder the 330 ohm resistor in series with the 1827 circuit. The resistor is non-directional.
