DTC C0040:64 (ZJ, ZY) [ABS]


id0402a7888800

DTC
C0040:64
Brake switch
DETECTION CONDITION
•  Brake switch ON signal is input for 6 min or more when driving at a vehicle speed of 20 km/h {12 mph} or more.
•  Brake switch ON signal is not input even though the control module determines vehicle deceleration.
POSSIBLE CAUSE
•  Open or short circuit in wiring harness between the brake switch terminal D and PCM terminal 1G
•  Brake switch malfunction
•  Poor connection at connectors (female terminal)

Diagnostic procedure

STEP

INSPECTION

ACTION

1
VERIFY OPEN OR SHORT CIRCUIT IN BRAKE SWITCH SIGNAL
•  Turn the ignition switch to the ON position.
•  Measure the voltage between the PCM terminal 1G (vehicle harness-side) and body ground when the brake pedal is depressed and released.
Voltage
Brake pedal depressed: B+
Brake pedal released: 1 V or less
Yes
Go to Step 5.
No
If it is B+ under any condition, then go to the next step.
If it is 1 V or less under any condition, then go to Step 3.
2
INSPECT BRAKE SWITCH SIGNAL FOR SHORT TO POWER SUPPLY CIRCUIT
•  Disconnect the brake switch connector.
•  Measure voltage between the brake switch connector terminal D (vehicle harness-side) and body ground.
•  Is the voltage 1 V or less?
Yes
Go to Step 4.
No
Repair or replace the wiring harness between the PCM and brake switch, then go to Step 5
3
INSPECT BRAKE SWITCH SIGNAL FOR OPEN CIRCUIT
•  Disconnect the PCM connectors.
•  Disconnect the brake switch connector.
•  Inspect continuity between the PCM connector terminal 1G (vehicle harness-side) and brake switch terminal D (vehicle harness-side).
•  Is there continuity?
Yes
Go to the next step.
No
Repair or replace the wiring harness between the PCM and brake switch, then go to Step 5.
4
INSPECT BRAKE SWITCH
•  Inspect the brake switch.
•  Is the brake switch normal?
Yes
Go to the next step.
No
Replace the brake switch, then go to the next step.
5
VERIFY THAT THE SAME DTC IS NOT PRESENT
•  Reconnect all disconnected connectors.
•  Clear the DTCs from the memory.
•  Start the engine and drive the vehicle at 20 km/h {12 mph} or more.
•  Are the same DTCs present?
Yes
Repeat the inspection from Step 1.
If the malfunction recurs, replace the ABS CM, then go to the next step.
No
Go to the next step.
6
VERIFY THAT NO OTHER DTCS ARE PRESENT
•  Are any other DTCs output?
Yes
Go to the applicable DTC inspection.
No
DTC troubleshooting completed.