Blower motor doesn’t work GM vehicles

Fix for Blower motor doesn’t work

GM has issued a service bulletin PIT5383C to address a blower motor doesn’t work condition on the vehicles listed below. There are multiple symptoms associated with this issue:

• The HVAC controls don’t work. Lights on the HVAC controls may blink or not even light up.

•  The HVAC controls don’t correspond to the HVAC state. For example, the temp may blow cold even when the setting is set to full hot. Or, it may blow air towards your feet when set to defrost mode. Or, the blower motor may not respond.

•  The A/C compressor may not engage or not follow driver commands.

•  The A/C compressor clutch engages but may not cool properly because the compressor solenoid valve is at 0% duty cycle even when cooling demands are high

•  Recirculation mode doesn’t work properly.

•  Heated or cooled seats don’t work (Cadillac and Corvette Models ONLY)

•  The battery saver message flashes on and off.

•  The vehicle battery is dead

•  A service heater message appears on the driver information center display.

•  A low coolant light or message is displayed.

•  The HVAC, IPC, turn signals, or any of the above issues may occur after the vehicle has been started using the remote start function or the vehicle may display any of these trouble codes:

•  B0163 B0183 B1405 B0173 B0178 B0509 B0514 B0519 B3583 B3933 B0193 B0208 B0223 B0228 B0233 B0408 B0413 B0418 B0423 B0428 B0433 B1395 B3531 B374A B3782 B393B B3925 U1501 U1510

Models affected by service bulletin PIT5383C

2015 Buick Encore (built before 4/4/15)
2015 Cadillac ATS, CTS (built before 2/26/15)
2015 Cadillac Escalade* (built before 1/30/15)
2015 Cadillac XTS (built before 2/18/15)
2015 Chevrolet Colorado (built before 1/30/15)
2015 Chevrolet Corvette (built before 3/19/15)
2015 Chevrolet Silverado 1500, Silverado 2500/3500* (built before: 1/8/15 if 11th VIN digit = “G”, 1/22/15 if 11th VIN digit = “Z”, 1/12/15 if 11th vin digit = “F”)
2015 Chevrolet Suburban*, Tahoe* (built before 1/30/15)
2015 GMC Canyon (built before 1/30/15)
2015 GMC Sierra 1500, Sierra 2500/3500* (built before: 1/8/15 if 11th VIN digit = “G”, 1/22/15 if 11th VIN digit = “Z”, 1/12/15 if 11th VIN digit = “F”)
2015 GMC Yukon Models* (built before 1/30/15)
* Only Utilities And 2500/3500 Pickup Trucks built with RPO AVF (Mid-Year 2015

 Fix for the above blower motor doesn’t work and other symptoms

Do NOT replace the HVAC control head. GM has issued a software update to correct the problem. Reprogram the vehicle using the latest software. If the problems disappear, you’re done. If they return, then perform the diagnostics shown in the shop manual.

HVAC reprogramming

HVAC reprogramming is not free. It can be performed by any shop that does reprogramming. It takes about an hour to perform the software update and you must pay the software access fee charged by GM. So the total cost should be around $200, far less than the cost of a replacement HVAC control head.

©, 2020 Rick Muscoplat