DTC P057D Brake Pedal Position Sensor "A" Circuit High: Notes

DTC detecting condition:

Excessive input signal value state of the brake stroke sensor continues for 0.2 seconds or more.

Trouble symptom:

Brake cannot be controlled.
Regenerative brake cannot be controlled.
Brake assist does not operate.
EyeSight functions (ACC/PCS) do not operate.

Wiring diagram:

Electronic controlled brake system Ref. to WIRING SYSTEM (CROSSTREK MODEL (HEV))>ELECTRIC CONTROL BRAKE SYSTEM .

Courtesy of SUBARU OF AMERICA, INC.

CHECK BRAKE PEDAL .
Check the brake pedal and brake stroke sensor. Ref. to BRAKE>BRAKE PEDAL .

Is the check result OK?

Yes: Go to 3.

No: Adjust the brake pedal and brake stroke sensor, and properly install the sensor. Go to 2.
CHECK DTC .
1. Using the Subaru Select Monitor, perform the clear memory of [Electric Brake Booster]. Ref. to COMMON (DIAG)>CLEAR MEMORY .
2. Read the DTC of [Electric Brake Booster] using the Subaru Select Monitor. Ref. to ELECTRIC BRAKE BOOSTER (DIAGNOSTICS)>DIAGNOSTIC TROUBLE CODE (DTC) .
  Is DTC P057D displayed?
  
  Yes: Go to 3.
  
  No: Finish the diagnosis.
CHECK CONNECTOR .
Check the connection status of the intermediate connectors (AD81, B652) and the brake stroke sensor connector.

Is there looseness, deformation, or corrosion at the connectors?

Yes: Repair or replace the connector.

No: Go to 4.
CHECK HARNESS .
1. Disconnect the coupling connector. (AD81, B652)
2. Disconnect the brake stroke sensor connector.
3. Measure the resistance between the intermediate connector and brake stroke sensor connector.
  Connector & terminal
  
  (B652) No. 13 - (B601) No. 4:
  
  (B652) No. 14 - (B601) No. 5:
  
  (B652) No. 15 - (B601) No. 6:
  
  Is the resistance less than 1 Ω?
  
  Yes: Go to 5.
  
  No: Repair or replace the harness.
CHECK HARNESS .
Measure the resistance between intermediate connector and chassis ground.

Connector & terminal

(B652) No. 13 - Chassis ground:

(B652) No. 14 - Chassis ground:

(B652) No. 15 - Chassis ground:

Is the resistance 10 kΩ or more?

Yes: Go to 6.

No: Repair or replace the harness.
CHECK BRAKE STROKE SENSOR .
1. Connect the coupling connector.
2. Turn the ignition switch to ON.
3. Measure the voltage at the brake stroke sensor connector.
  Connector & terminal
  
  (B601) No. 4 (+) - (B601) No. 5 (-):
  
  Is the voltage 4.84 - 5.16 V?
  
  Yes: Replace the brake stroke sensor. Ref. to BRAKE>BRAKE PEDAL .
  
  No: Go to 7.
CHECK HARNESS BETWEEN EBB CONTROL MODULE AND INTERMEDIATE CONNECTOR .
1. Remove brake booster assembly (with the master cylinder) from vehicle.
2. Disconnect the EBB control module connector.
3. Measure the resistance between EBB control module connector and intermediate connector.
  Connector & terminal
  
  (AD82) No. 21 - (AD81) No. 14:
  
  (AD82) No. 24 - (AD81) No. 15:
  
  (AD82) No. 32 - (AD81) No. 13:
  
  Is the resistance less than 1 Ω?
  
  Yes: Replace the brake booster assembly (with the master cylinder). Ref. to BRAKE>BRAKE BOOSTER .
  
  No: Repair or replace the harness.