OBD-II code · Network
U0324 Software Incompatibility with HVAC Control Module
The HVAC controller is running software incompatible with the rest of the network. Climate functions may default to a basic operating mode.
Is it safe to drive with U0324?
Usually safe to drive in the short term. Get it diagnosed when convenient, sooner if the car drives differently.
Common causes
- Most likelyIncompatible flash after HVAC swap
- Less likelyGateway module routing CAN messages incorrectly
- Less likelyCAN terminating resistor (120 Ω) drifted out of spec
Symptoms
- Multiple warning lights may illuminate
- Affected modules may go into limp mode or shut down
- Specific functions inoperative depending on module
- Diagnostic tools may show communication faults
Repair at a glance
- Difficulty
- Medium
- DIY friendly
- Best left to a mechanic
- Typical labour
- 0.3–2 h
- Emissions test
- Usually unaffected
- Parts involved
- HVAC Module
Related codes
- U0321Software Incompatibility With Suspension Control Module A
- U0322Software Incompatibility with Body Control Module B
- U0323Software Incompatibility With Instrument Panel Control Module
- U0325Software Incompatibility with Auxiliary Heater Control Module
- U0326Software Incompatibility With Vehicle Immobilizer Control Module
- U0327Software Incompatibility with Powertrain Control Module
Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.