Impact Sensor
A remote crash sensor — an accelerometer, or on some doors a pressure sensor — mounted at the extremities of the vehicle and reporting to the restraints control module. It exists because the restraints module sits in the most protected part of the structure and therefore feels an impact last, while an airbag has only tens of milliseconds to inflate. These sensors buy that time.
Which puts them in the most exposed part of the vehicle, on the bumper beam, in the front rails, inside doors and pillars, and at the rear — the wettest, most salted and most frequently repaired areas there are.
So the dominant failure is not electrical. It is disturbance during body repair. A sensor measures the motion of whatever it is bolted to, so orientation, torque and a clean flat mounting face are all part of the sensor: mounted backwards, under-tightened, or with paint, underseal or corrosion between it and the panel, it reads a genuine impact wrongly while passing every static test. Part numbers are not interchangeable between model years either.
Nothing on this system is worked on with the battery connected, and a resistor substituted for a sensor is never a repair.
Also known as: crash sensor, front impact sensor, side impact sensor, satellite sensor, airbag sensor, srs sensor, acceleration sensor
Referenced by 26 codes
Codes involving this component (26)
- U0152 Lost Communication With Side Restraints Control Module — Left High
- U0153 Lost Communication With Side Restraints Control Module — Right High
- U0170 Lost Communication With Restraints System Sensor A High
- U0171 Lost Communication With Restraints System Sensor B High
- U0172 Lost Communication With Restraints System Sensor C High
- U0173 Lost Communication With Restraints System Sensor D High
- U0174 Lost Communication With Restraints System Sensor E High
- U0175 Lost Communication With Restraints System Sensor F High
- U0176 Lost Communication With Restraints System Sensor G High
- U0177 Lost Communication With Restraints System Sensor H High
- U0178 Lost Communication With Restraints System Sensor I High
- U0179 Lost Communication With Restraints System Sensor J High
- U0336 Software Incompatibility With Restraints Control Module High
- U0452 Invalid Data Received From Restraints Control Module High
- U0453 Invalid Data Received From Side Restraints Control Module — Left High
- U0454 Invalid Data Received From Side Restraints Control Module — Right High
- U0471 Invalid Data Received From Restraints System Sensor A High
- U0472 Invalid Data Received From Restraints System Sensor B High
- U0473 Invalid Data Received From Restraints System Sensor C High
- U0474 Invalid Data Received From Restraints System Sensor D High
- U0475 Invalid Data Received From Restraints System Sensor E High
- U0476 Invalid Data Received From Restraints System Sensor F High
- U0477 Invalid Data Received From Restraints System Sensor G High
- U0478 Invalid Data Received From Restraints System Sensor H High
- U0479 Invalid Data Received From Restraints System Sensor I High
Other components in Body, Interior and Safety
- Body Control Module 299
- Restraints Control Module 177
- Air Conditioning Control Module 80
- Door Control Module 58
- Seat Belt Pretensioner 55
- Occupant Classification Module 33
- Audio Amplifier 28
- Seat Control Module 28
- Fuel Filler Door 26
- Steering Column Clockspring 24
- Steering Column Control Module 21
- Stop-Start Switch 20
- Door Switch 17
- Door Window Motor 10
- Air Conditioning Refrigerant Expansion Valve 7
- Instrument Cluster 6
- Moveable Roof Control Module 5
- Mirror Control Module 5
- Pedestrian Alert Module 3
- Front Radar Sensor 3
- Park Assist Module 3
- Remote Function Actuation Module 3
- Automated Driving System Control Module 2
- Seat Control Switch Module 2
- Speech Recognition Module 2
- Folding Top Control Module 1
- Heated Steering Wheel Module 1
- Haptic Control Module 1
Information, not instruction
CarGeek is a reference, not a service manual. Its pages are written from public sources and from what other people have found, never from a manufacturer's own service information, so they can be wrong or incomplete for your particular vehicle. Some of what they describe carries real risk: high voltage, fuel under pressure, stored energy, hot and moving parts.
Have anything you intend to act on checked by a trained person against the manufacturer's own procedure for your vehicle. Nothing here replaces that procedure.
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