U0466Invalid Data Received From HVAC Control Module - Rear
- Generic OBD-II code · Network
- How the car detects it
- U0466 concerns the rear HVAC control module, the second climate controller in vans, minivans and large SUVs that runs its own blower, blend flaps and often a separate control panel for the back rows. A receiver such as the front climate unit or the body controller sets the code when the rear module's frames carry bad checksums, stalled counters or settings it cannot accept. No manufacturer documents U0466 publicly. For the front unit GM describes the equivalent check in its 2025 body controller: counters, protection values and CRCs of the HVAC messages are tested every 10 ms, and 8 failures within 10 samples set U0424 as Type B. U0165 means the rear module is silent, U0424 covers bad data from the front unit. The rear zone then ignores its controls or holds a fixed setting, while engine and front climate stay normal; no MIL.
- What you may notice
- Rear climate controls do not respond
- Rear blower or temperature stuck at one setting
- Climate warning or fault message in the display
- Likely causes
- LikelyLoose or corroded connector at the rear HVAC module, often in the rear trim or headliner
- PossibleSoftware mismatch after replacing or programming one of the climate modules
- PossibleWeak battery or voltage dips at the module
- RareInternal fault in the rear HVAC control module
- Repair
- Medium · Usually a job for a workshop.Typical cost: €50 – €700
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.