PIT5292

Bulletin No.: PIT5292
Date: May-2014
Subject:
A/C Blows Warm During High Ambient Temperatures
Models:
2015 Cadillac Escalade Models
2015 Chevrolet Suburban, Tahoe
2015 GMC Yukon Models
The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.
Condition/Concern
Some owners may comment that the A/C is inoperative. This concern may only occur during high ambient temperatures. When using GDS2 to review reasons
for A/C compressor disengagement, it may indicate an A/C high pressure issue. This concern may be caused by one of the following issues:
1.
A/C high side pressure sensor connector not fully seated or poor terminal tension
2.
A/C refrigerant has been overcharged
3.
A/C high side pressure sensor reading may be skewed
Recommendation/Instructions
1.
Check the A/C high side pressure sensor connector for proper terminal tension and to make sure that it is fully connected. Repair as
necessary.
2.
Check the A/C refrigerant charge. System capacity is 2.0 lbs. If system charge is found to be incorrect, recharge system to 2.0 lbs.
3.
Connect a set of A/C pressure gages to the vehicle and open GDS2. Compare the high side pressure gage reading to the A/C high side pressure
sensor reading in GDS2. Monitor the pressure when first connected to the vehicle while the system is off, and also while the A/C is operating. The high
side gage reading and the data displayed in GDS2 should read relatively close. If the readings vary greatly, a wiring concern may be present or the
sensor may be skewed. Repair any wiring issues present or, if none found, replace the A/C high side pressure sensor.
Warranty Information
The correction for this concern may be one of several repairs described above. For vehicles repaired under warranty, please use the appropriate warranty
labor operation based on the actual cause and repair.
ADDITIONAL SI KEYWORDS:
AC HVAC
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.
GM bulletins are intended for use by professional technicians, NOT a "do-it-yourselfer". They are written to inform these technicians of conditions that may
occur on some vehicles, or to provide information that could assist in the proper service of a vehicle. Properly trained technicians have the equipment, tools,
safety instructions, and know-how to do a job properly and safely. If a condition is described, DO NOT assume that the bulletin applies to your vehicle, or that
your vehicle will have that condition. See your GM dealer for information on whether your vehicle may benefit from the information.
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