U0551Invalid Data Received From Impact Classification System Module
- Generic OBD-II code · Network
- How the car detects it
- An impact classification system module helps the restraint system judge what kind of collision is under way, for example frontal, side or angled, and how severe it is, so that the right airbags and pretensioners fire at the right stage. U0551 means another module, typically the airbag or restraint controller, receives messages from this unit whose content fails its plausibility or integrity checks. No manufacturer has published a description or setting criteria for this code. Patents on bus-connected crash sensing such as US7832762 show why such traffic is protected: deployment decisions travel over the network to the protection devices. With the classification input in doubt, the airbag warning lamp comes on and the system cannot rely on that information. Treat it as a safety fault; a silent module gives U0250.
- What you may notice
- Airbag/SRS warning lamp on
- Restraint system message in the instrument cluster
- Passenger airbag status indicator behaving abnormally
- Likely causes
- PossibleInternal fault in the impact classification module
- PossibleModule or restraint controller not configured/programmed after replacement or crash repair
- RareDamaged wiring or connector after collision or interior work
- Repair
- Workshop only · Usually a job for a workshop.Typical cost: €100 – €900
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.