The GMC Yukon XL has had several technical service bulletins (TSB) published on every model year of the Yukon. These TSBs cover wiring, electrical, blower and climate-control problems as well as many other issues found in the Yukon. The air-conditioning problems in the Yukon can also include the fuse and thermostat problems some GMC owners are experiencing.
A TSB has been published by the manufacturer of the Yukon XL concerning wiring harness issues that affect the operation of the AC unit in the GMC. The wiring harness is chafing, causing electrical issues with the thermostat, AC compressor and climate controls of the Yukon. Chafing of the wiring harness prevents voltage from flowing to one or all of these AC components, causing them not to work. The chafing of the wiring harness can also cause the AC components to work intermittently. The TSB recommends that the wiring harness be replaced, because another TSB has been published on the Yukon about wiring splices on the wiring harness not fixing electrical problems.
Another TSB has been published on the Yukon XL about the fuses and circuit breaker problems on the GMC. The fuses that control several engine components including the AC compressor are blowing, causing the components not to work. The fuse and circuit breakers in the Yukon XL prevent damage from occurring to the AC components by blowing when there is an overload of voltage. The fuses are blowing because of the wiring harness problems found in the Yukon XL. These fuses must be replaced, as well as the wiring harness, to prevent this AC problem.
The AC blower motor is not working properly in the Yukon XL. The TSB published by the manufacturer states that the blower motor stops working or continues to run in low temperatures. This AC problem is attributed to improper insulation of the motor and motor connection, causing the motor to freeze and preventing the motor from operating. The improper insulation can also freeze the connection closed, preventing the blower motor from shutting off and allowing it to continue to operate even when the climate control switch is turned off. The only correction for this AC problem in the Yukon XL is to replace the blower motor.
