Bus (+/-) Signals Open/No Response From AZC Module

Tests 1 - 3:

Tests 4 - 5:

SYMPTOM
BUS +/- SIGNALS OPEN OR NO RESPONSE FROM AUTOMATIC ZONE CONTROL MODULE

POSSIBLE CAUSES
- Attempt to communicate with the BCM
- Fused B(+) circuit open
- Fused ignition switch output circuit open
- Open PCI bus circuit
- Automatic zone control module