Symptom

There may be a chirp noise coming from the front of the dash on the passenger side.

Possible Cause

The HVAC air inlet seal (1) may not be fully seated against the front of the dash sheet metal.

Diagnosis

1. Remove the pollen filter. Refer to Passenger Compartment Air Filter Replacement in HVAC Systems with A C - Manual.
2. Remove the I/P trim pad. Refer to Instrument Panel Trim Pad Replacement in Instrument Panel, Gauges and Console.
3. Reach through the Pollen filter access hole and verify there is a gap between the HVAC air inlet seal (1) and the front of the dash sheet metal.

Corrective Action

Carefully move the HVAC to maximize the amount of clearance between the seal (1) and the front of the dash sheet metal. once you have obtained a small gap, lubricate the HVAC air inlet seal (1) with dielectric grease GM P/N 12345579.

Symptom

There may be a chirp noise coming from the front of the dash area.

Possible Cause

The HVAC air inlet grille (1) may be contacting the lower edge of the windshield (2).

Diagnosis

Isolate the HVAC air inlet grille (1) at the locations indicated with a piece of paper. Record any changes heard.

Corrective Action

Attach a piece of 1-2 mm (0.039-0.079 in) thick foam tape to the back side of the HVAC air inlet grille (1) at the points of contact on the windshield (2).