Bus (+/-) Signals Open From ATC Module

Tests 1 - 3:

Tests 4 - 5:

SYMPTOM
BUS +/- SIGNALS OPEN 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