HVAC Blower Motor May Run Continuously After Vehicle is Turned Off (Replace Blower Resistor Relay)
| Subject: | HVAC Blower Motor May Run Continuously After Vehicle is Turned Off (Replace Blower Resistor Relay) |
| Models: | 2004 Chevrolet Avalanche, Silverado, Suburban, Tahoe, TrailBlazer, TrailBlazer EXT |
| 2004 GMC Envoy, Envoy XL, Sierra, Yukon, Yukon XL |
| with Manual Control HVAC (RPO CJ3) |
| Built Prior to August, 2003 |
Condition
Some customers may comment on the HVAC blower motor running after the vehicle has been turned off. The blower may run for just a few minutes or continuously until the battery is discharged.
Cause
A new style HVAC blower relay/resistor may stick in the "on" position. When the HVAC fan blower relay has been energized, the contacts may "micro-weld" together. After this occurrence, the HVAC blower may not respond to the HVAC controller commands.
Correction
Replace the HVAC blower resistor/relay with the type used previous to the 2004 model year. The appropriate part numbers are listed in the table below. For specific repair procedures, refer to the 2004 Service Information (SI) under Blower Motor Resistor Assembly Replacement (SI Document ID #526350 (C/K) or #729996 (S/T).
Parts Information
Part Number | Description |
|---|---|
15305077 | Relay, Blower Motor Resistor (C/K) |
15415789 | Relay, Blower Motor Resistor (S/T) |
Parts are currently available from GMSPO.
Warranty Information
For vehicles repaired under warranty, use:
Labor Operation | Description | Labor Time |
|---|---|---|
D1002 | Resistor, Blower Motor - Replace | 0.3 hr |
