DTC P0555-00: Brake Booster Pressure Sensor (running); DTC P0555-2A: Brake Booster Pressure Sensor Signal Stuck In Range [11/2021 - 03/2023]: Description
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The engine stop and start ECU determines changes in the brake booster assembly pressure based on the voltage signal received from the vacuum sensor assembly in the brake booster assembly.
If the output value of the vacuum sensor assembly remains the same even though the brake booster assembly pressure changes when the brake pedal is operated or the vehicle is being driven, the engine stop and start ECU judges that the sensor is stuck.
When sticking of the sensor is detected, the engine stop and start ECU stores DTC P0555-00 or P0555-2A and blinks the stop and start cancel indicator light.
| DTC No. | Detection Item | DTC Detection Condition | Trouble Area | Warning Indicate | Memory | Note |
|---|---|---|---|---|---|---|
| P0555-00 | Brake Booster Pressure Sensor (running) | The change in vacuum while stopping the vehicle 30 times from a speed of 30 km/h (19 mph) or more was 0.3 kPa (2 mmHg, 0.09 in.Hg) or less (1 trip detection logic). |
|
Blinks | DTC stored | SAE Code: P0556 |
| P0555-2A | Brake Booster Pressure Sensor Signal Stuck In Range | The change in vacuum is 0.3 kPa (2 mmHg, 0.09 in.Hg) or less more than 3 times when the brake pedal is firmly depressed to stop the vehicle (deceleration of 0.15 G or more for 1 second or more) (1 trip detection logic). |
|
Blinks | DTC stored | SAE Code: P0556 |