B0029
Left Front Impact Sensor Signal Incorrect
Criticalsensor
Overview
The B0029 diagnostic trouble code indicates that the body control module has identified a left front impact sensor signal incorrect issue. This code means a body sensor or its circuit is not providing expected readings. Accurate sensor data is important for proper operation of safety and convenience systems throughout the vehicle.
Symptoms
- Passenger airbag off indicator lit unexpectedly
- Window pinch protection not functioning
- SRS malfunction indicator illuminated
- Convertible top position incorrectly detected
Common Causes
- Physical obstruction blocking sensor
- Temperature sensor failure
- Damaged sensor wiring or connector
- Failed rain or ambient light sensor
Diagnosis Steps
- 1Connect an OBD-II scanner and read all stored body control module trouble codes
- 2Inspect the affected sensor and its wiring connector for damage or corrosion
- 3Test the sensor resistance or voltage output with a multimeter
- 4Check for physical obstructions, contamination, or misalignment of the sensor
- 5Verify sensor calibration using scan tool where applicable
Estimated Repair Cost
$50 — $400
Cost varies by vehicle, location, and repair shop. Includes parts and labor.
Commonly Affected Vehicles
Hyundai TucsonHonda CR-VToyota CorollaKia Sportage
Related Codes
More Sensor Codes
P0070Ambient Air Temperature Sensor Circuit
LowP0071Ambient Air Temperature Sensor Range/Performance
LowP0072Ambient Air Temperature Sensor Circuit Low
LowP0073Ambient Air Temperature Sensor Circuit High
LowP0074Ambient Air Temperature Sensor Circuit Intermittent
LowP0095Intake Air Temperature Sensor 2 Circuit
LowFrequently Asked Questions
A stuck or misaligned door ajar switch is the most common cause. The switch is located in the door latch mechanism and can be cleaned or replaced for $20-$100.