ATC Recirculation Switch Failure
NOTE:
After making any repairs, perform BODY VERIFICATION TEST
under VERIFICATION TESTS.
Monitored & Set Condition
- When Monitored: With the ignition on.
- Set Condition: The BCM interfaces with the ATC head over the PCI Bus. If any ATC switch is held in the closed position for longer than 5-10 minutes, a switch failed code will be set.
Possible Causes:
- ATC Head Switch Stuck
- ATC Head - Erase DTC - Reset
Testing
- Turn ignition on. With the scan tool select Automatic Temp Control, Input/Output and observe the switch state. If any of the switch states read CLOSED, replace the automatic temperature control head. See AUTOMATIC A/C-HEATER SYSTEMS - CONCORDE, INTREPID & 300M article in HVAC. If any of the switch states do not read CLOSED, use the scan tool to erase the trouble code and reset the module using scan tool.