Lost Communication With HVAC Control Module
What does U0164 mean?
The U0164 code means the vehicle's onboard diagnostic system has detected: Lost Communication With HVAC Control Module. This is a low severity code.
Common Symptoms
- HVAC system inoperative
- Climate control does not respond
- Blower motor may not work
- Temperature control not functioning
Probable Causes (Ranked by Likelihood)
- Failed HVAC control module Very High
- CAN bus wiring fault to HVAC module High
- HVAC module connector corrosion Moderate
- HVAC module power supply loss Low
Step-by-Step Diagnostic Procedure
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Check HVAC module power and ground
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Inspect HVAC module connector behind the dashboard
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Verify CAN bus wiring to HVAC module
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Check blower motor and blend door actuators independently
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Replace HVAC module if communication lost
Frequently Asked Questions
Can I drive with code U0164?
Yes, you can drive. Lost communication codes indicate a module has stopped communicating on the vehicle network. The affected system may not function correctly.
What causes U0164?
The most common cause is a failed module or a wiring issue in the CAN bus network. Failed HVAC control module is the most likely cause. Power supply, ground, and connector issues should be checked before replacing any module.
Is U0164 expensive to fix?
Repair costs range from $100 - $600 (parts and labor). Wiring repairs are on the lower end, while module replacement is on the higher end. The module may also need to be programmed after replacement.