Turn the ignition switch OFF.
Disconnect the temperature control actuator connector.
Verify that the temperature control actuator operates to the warm position when connecting 12V to terminal 3 and grounding terminal 4.
Verify that the temperature control actuator operates to the cool position when connected in reverse.
1. - 2. - 3. Warm position 4. Sensor ground | 5. Feedback Signal 6. Sensor (+5V) 7. Cool position |
Connect the temperature control actuator connector.
Turn the ignition switch ON.
Check the voltage between terminal 4 and 5.
Door position | Voltage (V) | Error detecting |
Max. cooling | 0.3 ± 0.15V | Low voltage : 0.1V or less |
Max. heating | 4.7 ± 0.15V | High voltage : 4.9V or more |
It will feedback the current position of the actuator to the controls.
If the measured voltage is not specification, substitute with a known-good temperature control actuator and check for proper operation.
If the problem is corrected, replace the temperature control actuator.