Bus +/- Signals Open or No Response From Automatic Temperature Control Module

Test 1 - 3:

Test 4 - 5:

SYMPTOM
*BUS +1- SIGNALS OPEN OR NO RESPONSE FROM AUTOMATIC TEMPERATURE CONTROL MODULE


POSSIBLE CAUSES
- Attempt to communicate with the BCM
- Fused ignition switch output circuit open
- Ground circuit open
- Automatic temperature control head
- PCI bus circuit open
- Body control module