DTC C1446 [DSC/RSC]

id0402b3803400

DTC | C1446 | Brake switch system
DETECTION CONDITION | • Brake switch ON signal is not input when the brake fluid pressure sensor signal reaches the specified value. • Brake switch ON signal is input even if the signal from the brake fluid pressure sensor is less than the specification.
POSSIBLE CAUSE | • Open or short circuit in wiring harness between the brake switch and PCM 1T terminal (PCM CONNECTOR (2 TYPES)) • Open or short circuit in wiring harness between the brake switch and PCM 1S terminal (PCM CONNECTOR (3 TYPES)) • Brake switch malfunction • DSC/RSC HU/CM 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 following PCM terminals and body ground when the brake pedal is depressed and released: ― 1T (PCM CONNECTOR (2 TYPES)) ― 1S (PCM CONNECTOR (3 TYPES)) Voltage Brake pedal depressed: B+ Brake pedal released: 1 V or less • Is the voltage normal? | 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 the 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 following PCM connector terminal (vehicle harness-side) and brake switch terminal D: ― 1T (PCM CONNECTOR (2 TYPES)) ― 1S (PCM CONNECTOR (3 TYPES)) • 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. (See BRAKE SWITCH INSPECTION.) • Is the brake switch normal? | Yes | Go to the next step.
No | Replace the brake switch, then go to the next step. (See BRAKE PEDAL REMOVAL/INSTALLATION [L.H.D.].) (See BRAKE PEDAL REMOVAL/INSTALLATION [R.H.D.].)
5 | VERIFY THAT THE SAME DTC IS NOT PRESENT • Reconnect all disconnected connectors. • Clear the DTCs from the memory. (See ON-BOARD DIAGNOSIS [DSC/RSC].) • Are the same DTCs present? | Yes | Repeat the inspection from Step 1. If the malfunction recurs, replace the DSC/RSC HU/CM, then go to the next step. (See DSC/RSC HU/CM REMOVAL/INSTALLATION [L.H.D.].) (See DSC/RSC HU/CM REMOVAL/INSTALLATION [R.H.D.].)
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. (See ON-BOARD DIAGNOSIS [DSC/RSC].)
No | DTC troubleshooting completed.