Diesel Data: Automotive Repair

Blower Fan Runs Slower Than Expected In Cold Weather (When In AUTO Mode) (With Climate Control)




Blower fan runs slower than expected in cold weather (when in AUTO mode)

Diagnostic Procedure:

1. Probable cause: Engine coolant temperature (ECT) circuit malfunction

2. Troubleshoot the ECT sensor circuit:

Also check for:

- ECT sensor 2 circuit low voltage P2184
- ECT sensor 2 circuit high voltage P2185
- HVAC DTCs How to Troubleshoot the Climate Control System
- Powertrain DTCs Initial Inspection and Diagnostic Overview
- Blower motor operation