Front Blower Motor Inoperative or May Not Shut Off In Extremely Low Ambient Temperature Conditions (Replace Blower Motor Control Module)
| Subject: | Front Blower Motor Inoperative or May Not Shut Off in Extremely Low Ambient Temperature Conditions (Replace Blower Motor Control Module) |
| Models: | 2004-2007 Buick Rainier |
| 2004-2006 Cadillac Escalade Models |
| 2004-2006 Chevrolet Avalanche, Silverado, Suburban, Tahoe |
| 2004-2007 Chevrolet TrailBlazer Models |
| 2007 Chevrolet Silverado (Classic) |
| 2004-2006 GMC Sierra Models, Yukon Models |
| 2004-2007 GMC Envoy Models |
| 2007 GMC Sierra (Classic) |
| 2004-2006 HUMMER H2 Models |
| with Automatic Temperature Control HVAC System (RPO CJ2) |
This bulletin is being revised to include the 2007 Silverado/Sierra (Classic) and midsize utility models. Please discard Corporate Bulletin Number 06-01-39-002A (Section 01 -- HVAC).
Condition
Some customers may comment that the front blower motor is inoperative or continues to run after the vehicle has been shut off.
Cause
These conditions may be caused by a blower motor control module failure. This failure will only occur when the vehicle is operated in ambient temperature conditions of -23°C (-10°F) or below. GM expects most failures to occur in Alaska or northern Canada. Dealers outside of the regions where extremely cold temperatures are encountered should NOT order the part listed below. Dealers outside of cold weather regions that install this part will be subject to warranty claim review.
Correction
Important: Replace the blower motor control module ONLY if the vehicle experienced a blower motor control module failure in extremely cold ambient temperature conditions. This information DOES NOT apply to any other blower motor conditions.
Technicians are to replace the blower motor control module, also called the Linear Power Module (LPM), with the P/N listed below. Refer to either the Blower Motor Control Processor Replacement or Blower Motor Processor Replacement-Auxiliary procedures in SI. After replacement of the blower motor control module, the customer may notice a slightly higher than expected blower motor speed at any of the blower speed settings.
Parts Information
Part Number | Description | Qty |
|---|---|---|
89018849 | Module Assembly, Auxiliary Blower Motor Control (Rear System on Escalade ESV, Suburban, Yukon XL) | 1 |
89018964 | Module, HTR & BLO & A/C CONT (Front system only vehicles - Except H2) | 1 |
89023355 | Module Assembly, Blower Motor Control (H2 models) | 1 |
89024926 | Module Assembly, Auxiliary Heater & A/C Control (Rear System on Escalade, Yukon, Tahoe) | 1 |
Warranty Information
For vehicles repaired under warranty, use:
Labor Operation | Description | Labor Time |
|---|---|---|
D0890 | Module, Blower Motor Control - Replace | Use Published Labor Operation Time |
Add | Diagnostic Time |
