PIC5965

Bulletin No.: PIC5965
Date: Feb-2014
Subject:
Diagnostic Tip - Various Heating and Cooling Concerns With HVAC Control Module DTC U1510
Models:
2014 Chevrolet Camaro
The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.
Condition/Concern
Some customers may comment on a wide variety of HVAC concerns for the vehicle listed above. During diagnosis, a technician will find a current or history
DTC U1510 set in the K33 HVAC Control Module. This DTC will set for a loss of communication with the A20 Radio / HVAC controls on the LIN Bus.
Recommendation/Instructions
It has been found through warranty reviews that many HVAC modules have simply been reprogrammed for various HVAC issues if the original customer's
concern was not able to be duplicated in the dealership setting. While there is an updated calibration for the HVAC module in these vehicles, by performing an
update alone, this will not address the loss of communication DTC that was set in the system. In many cases the vehicle was returned to the customer with only
the update being performed.
Instead, dealership technicians are asked to carefully inspect the connections at the HVAC control module, which is located next to the blower motor under the
passenger side of the dash. Carefully inspect both connectors to make sure they are fully seated. Then, inspect terminal tension using the appropriate
diagnostic test probes; currently J-35616-16 (L-GN) and J-35616-64B (L-BU) for connectors 1 and 2, respectively. Replace any loose terminals as needed.
If no issues are found, flex the wiring harness in an attempt to duplicate the concern with the system. If still no issues are found, technicians are to carefully
remove the radio faceplate from the radio itself and check the direct connections at that location.
Warranty Information
For wiring repairs covered under warranty, please refer to latest version of bulletin 10-00-89-005 for warranty information on wire/connector repairs.
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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