Supplement to Bulletin 04-01-38-012D Noise Heard when A/C is On - keywords AC air conditioning core evaporator flow hum HVAC pipe refrigerant valve whistle
| Subject: | Supplement to Bulletin 04-01-38-012D Noise Heard When A/C is On |
| Models: | 2004-2005 Chevrolet Colorado |
| 2004-2005 GMC Canyon |
This PI has been revised to reflect the new bulletin number 04-01-38-012D. Please discard PIT3982.
The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.
Condition/Concern:
Supplement to bulletin 04-01-38-012D, Whistle/Hiss/Hum/Ring Noise Heard When A/C is On.
The information will assist with the routing of the new AC pipe.
Recommendation/Instructions:
When installing the new AC tube part number 89024923, the tube will leave the evaporator core, route along the right frame rail, turn left in front of the condenser and attach to the receiver dryer. The original pipe that routed along the left side of the engine compartment and the small extension pipe that attached to the received dryer are both to be eliminated. Please inspect a 2006 Colorado or Canyon to clarify the new AC tube routing; all 2006 vehicles were manufactured with this change. Please use the refrigerant charge of 1.6lb (0.73kg) of R-134A.
Please follow this diagnostic or repair process thoroughly and complete each step. If the condition exhibited is resolved without completing every step, the remaining steps do not need to be performed.
