Intermittent Poor AC Performance Or Vapor From Vents - keywords air blower compressor condition core evaporator freeze hot HVAC intermittent sensor temperature

This PI was superseded to update models and model years. Please discard PIT3689A.

The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.

Intermittent poor A/C performance and/or a mist/vapor coming out of vents when the A/C is on. The evaporator core may be freezing. The temperature sensor in the thermal expansion valve (TXV) controls cycling of the compressor clutch to prevent freezing of the evaporator core. There is a cavity on the TXV that the temperature sensor sits in when bolted on. This cavity must be filled with thermal grease to get an accurate temperature reading. If the cavity does not have enough thermal grease, the temperature reading will not be accurate and the compressor will not cycle off to prevent freezing of the evaporator core.

Note: DO NOT perform this repair on a 2006 or 2007 Equinox.

To resolve this concern, the temperature sensor cavity on the TXV must be filled with thermal grease P/N 22668050. Use the instruction in SI for the (Air Conditioning (A/C) Refrigerant Low Temperature Sensor Replacement). This document will have the removal and installation procedures for the temperature sensor.

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.