PIT5200

Bulletin No.: PIT5200
Date: Feb-2013
Subject:
HVAC Blows Cold Due To Low System Voltage
Models:
2010 - 2012 Chevrolet Equinox
2010 - 2012 GMC Terrain
The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.
Condition/Concern
Customers may comment on the HVAC system will just start blowing cold air. This condition was found on the C68 auto HVAC system. Example: Customer set
temperature to 76 degrees F and while driving the HVAC changes to cold and unable to increase temperature when moved to full hot. During diagnostic, no
DTCs or possible B101E symptom 4B. The DTC B101E is set when a temperature or mode actuator has lost is its learn position or out of range. This concern
happens when the system voltage is low.
Recommendation/Instructions
Recent field cases found the cause to be low system battery voltage due to corrosion at the starter connections.
For vehicles that exhibit this condition and when the condition is present, use GDS and select "Remote Heater and Air Conditioning Module", select "HVAC
System Data", and check the "Ignition Voltage." If voltage is less than 12 volts, inspect for signs of corrosion at the starter stud battery cable connections.
Clean and recheck battery charging voltage.
Warranty Information
For vehicles repaired under warranty use:
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Labor Operation
Description
Labor Time
* N9701
Check Ignition Voltage and Clean Positive Battery Cable Terminal at Starter
0.3 hr
*This is a unique labor operation for bulletin use only. It will not be published in the Labor Time Guide.
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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