Whistle/Hiss/Hum/Ring Noise Heard When A/C is On (Replace Evaporator Core and Liquid Line)
| Subject: | Whistle/Hiss/Hum/Ring Noise Heard When A/C is On (Replace Evaporator Core and Liquid Line) |
| Models: | 2004-2005 Chevrolet Colorado |
| 2004-2005 GMC Canyon |
| with Air Conditioning (RPO C60) |
This bulletin is being revised to update the labor time information. Please discard Corporate Bulletin Number 04-01-38-012C (Section 01 -- HVAC).
Condition
Some customers may comment on a whistle/hiss/hum/ring noise that is heard inside the vehicle. The noise emanates from the compartment area of the instrument panel (IP) when the air conditioning (A/C) is on. Technicians may hear the noise every 15-60 seconds and the noise lasts for 2-5 seconds. The noise occurs when the A/C compressor cycles on. This condition does not indicate a defect in the A/C system, but the noise may be objectionable to the customer.
Cause
This condition may be caused by refrigerant flow through the evaporator core when the A/C compressor cycles on during normal operation.
Correction
Technicians are to replace the evaporator core and liquid line with updated design parts. Replace the evaporator core with P/N 89018834. Refer to the Evaporator Core Replacement procedure in the HVAC section of SI. Replace the evaporator tube (liquid line) with P/N 89024923. Refer to the Evaporator Tube Replacement procedure in the HVAC section of SI.
Parts Information
Part Number | Description | Qty |
|---|---|---|
89018834 | Evaporator Assembly-A/C | 1 |
89024923 | Tube Assembly, A/C Evaporator | 1 |
Warranty Information
For vehicles repaired under warranty, use:
Labor Operation | Description | Labor Time |
|---|---|---|
D9720* | Replace Evaporator Core and Liquid Line | 5.3 hrs |
*This is a unique labor operation number for bulletin use only. This number will not be published in the Labor Time Guide. | ||
