GM Releases Fix For Chevy Silverado Heater Auxiliary Coolant Pump Issue3
GM has released a service update for certain units of the 2020 through 2021 Chevy Silverado 1500 and 2022 Chevy Silverado 1500 Limited pickup over an issue related to the heater auxiliary coolant pump.
The problem: in affected units of the 2020 – 2021 Chevy Silverado 1500 and 2022 Chevy Silverado 1500 Limited pickup equipped with a manual HVAC system (RPO code CP4), the HVAC Control Module (RPO code K33) may not activate the auxiliary coolant pump during engine auto stop events, which is required to maintain the cabin heater temperature.
The hazards: this issue does not pose a safety hazard. However, it may affect the comfort of passengers in the cabin.
The fix: GM dealer technicians are instructed to reprogram the K33 HVAC Control Module with updated software in order to correct the issue.
Affected components: HVAC Control Module (RPO code K33).
- 2020 Chevy Silverado 1500
- 2021 Chevy Silverado 1500
- 2022 Chevy Silverado 1500 Limited
Number of affected vehicles: it’s unclear exactly how many vehicles are affected by this GM Service Bulletin.
Owners should: GM will notify owners of affected vehicles and instruct them to make an appointment with their dealers. Owners that are unsure as to whether or not their vehicle is affected by this service bulletin can reach out to GM directly with any questions or concerns they may have using the Service Update number and contact information listed below.
- Service Update number: N222375000
- Chevrolet Customer Service: 1-800-222-1020
As a reminder, the 2020 Chevy Silverado 1500, 2021 Chevy Silverado 1500, and 2022 Chevy Silverado 1500 Limited were offered with a wide range of powerplant options depending on the model year, including the naturally aspirated 4.3L V6 LV3 gasoline engine, turbocharged 2.7L I4 L3B gasoline engine, naturally aspirated 5.3L V8 L82 gasoline engine, naturally aspirated 5.3L V8 L84 gasoline engine, naturally aspirated 6.2L V8 L87 gasoline engine, and finally, the 3.0L I6 LM2 turbodiesel Duramax engine.
The GM T1 platform provides the underpinnings.
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I would rather disable the start-stop feature.