U0165low severityNetwork
Lost Communication with Rear HVAC Control Module
on 2001 Cadillac DeVille 4.6L V8 Northstar · FWD
What this code means
Cannot communicate with the rear climate control zone module.
Symptoms
- Rear A/C not working
- Rear climate controls unresponsive
- No rear heat
- Rear blower not running
Common causes
- Rear HVAC module failure
- CAN bus wiring
- Module power loss
- Fuse blown
- Rear blower motor issue
Diagnostic steps
- Check rear HVAC module fuse
- Test power and ground
- Check CAN wiring
- Test rear blower motor
- Inspect rear climate control panel
Repair notes
Check fuses for rear HVAC system. Rear module wiring runs through pillars.
Other Network codes on this vehicle
U0001
High Speed CAN Communication Bus
U0002
High Speed CAN Communication Bus Performance
U0003
High Speed CAN Communication Bus (+) Open
U0004
High Speed CAN Communication Bus (+) Low
U0005
High Speed CAN Communication Bus (+) High
U0006
High Speed CAN Communication Bus (-) Open
U0007
High Speed CAN Communication Bus (-) Low
U0008
High Speed CAN Communication Bus (-) High
U0009
High Speed CAN Communication Bus Shorted Together
U0010
Medium Speed CAN Communication Bus