U0164low severityNetwork
Lost Communication with HVAC Control Module
on 1998 Audi A6 2.8L V6 · AWD
What this code means
Cannot communicate with the climate control module.
Symptoms
- Climate control not working
- No A/C
- Fan not responding
Common causes
- HVAC module failure
- Fuse
- CAN bus
- Wiring
Diagnostic steps
- Check fuses
- Test power
- Check CAN wiring
Repair notes
Check fuses and power supply.
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Other Network codes on this vehicle
01314
Engine Control Module (ECM) - no communications
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