Inspection Procedure 3

INSPECTION PROCEDURE 3: A/C outlet air temperature cannot be set

CIRCUIT OPERATION
When the blower air temperature can not be changed even if the preset temperature is changed, the sensors, the air mixing damper control motor and potentiometer or the A/C-ECU may be defective.

TROUBLESHOOTING HINTS
- Malfunction of the A/C-ECU

DIAGNOSIS

Scan tool MB991958 diagnostic trouble code

Q: Is the diagnostic trouble code set?

YES: Refer to diagnostic trouble code chart. Diagnostic Trouble Code Descriptions

NO: Replace the A/C-ECU.