Fault Code 4

If both codes 4 and 5 appear at the same time, proceed with both tests. There is usually only one failure.

1. Remove terminal #4 from the 21-way Control Module connector and retest the system.
NOTE: This may cause other codes to be generated. These codes should be disregarded at this time.
- If code 4 reappears, replace the Control Module.
- If code 4 does not reappear, go to step 2.
2. Remove the 21-way Control Module connector and check for continuity between terminal #4 and ground.
- If there is continuity, repair the wiring.
- If there is no continuity, go to step 3.
3. Check for resistance between terminals #4 and #5, #4 and #6, and #4 and #15. Resistance should be between 20 and 50 ohms.
- If resistance is incorrect, replace the blend door actuator.