Stoplight switch system check (BCM)

1. Body control system check

Refer to "64.Body Control 10I.Troubleshooting(BCM) diagnostic system check-body controls".

2. Stop light switch signal check

1) Turn OFF the ignition switch.

2) Turn ON the ignition switch.

3) Observe the Brake Lamp Switch (M02-20) parameter while depressing and releasing the brake pedal repeatedly. Does the Brake Lamp Switch (M02-20) parameter match the brake pedal operation?

Yes

The system is normal.

No (Normally ON)

=>Go to Inspection for short circuit in stop light switch.

No (Normally OFF)

=>Go to Fuse inspection.

3. Fuse inspection

1) Inspect the STOP 10A fuse. Is the result normal?

Yes

=>Go to Inspection for open circuit in stop light switch.

No

Replace the fuse. If the fuse blows out again, repair the short to ground in the circuits relating to the fuse.

=>Go to Repair verification.

4. Inspection for open circuit in stop light switch

1) Inspect the stop light switch. Is the result normal?

Refer to "4.Brakes 4B.Brake System stoplight switch inspection".

Yes

=>Go to Inspection for open circuit in stop light switch power supply circuit.

No

Replace the stop light switch.

Refer to "4.Brakes 4B.Brake System stoplight switch removal".

Refer to "4.Brakes 4B.Brake System stoplight switch installation".

=>Go to Repair verification.

5. Inspection for short circuit in stop light switch

1) Turn OFF the ignition switch.

2) Disconnect the stop light switch harness connector (C68).

Refer to "LHD Body Control" in the ETM (wiring diagram). (Open using the ETM viewer.).

Refer to "RHD Body Control (4JJ3 with DPD)" in the ETM (wiring diagram). (Open using the ETM viewer.).

Refer to "RHD Body Control (4JJ3 without DPD, RZ4E)" in the ETM (wiring diagram). (Open using the ETM viewer.).

3) Turn ON the ignition switch.

4) Observe the Brake Lamp Switch (M02-20) parameter on the scan tool. Does the Brake Lamp Switch (M02-20) parameter show OFF?

Yes

Replace the stop light switch.

Refer to "4.Brakes 4B.Brake System stoplight switch removal".

Refer to "4.Brakes 4B.Brake System stoplight switch installation".

=>Go to Repair verification.

No

=>Go to Inspection for short to power supply in stop light switch signal circuit.

6. Inspection for open circuit in stop light switch power supply circuit

1) Turn OFF the ignition switch.

2) Disconnect the stop light switch harness connector (C68).

3) Connect a test lamp between the stop light switch harness connector (pin 1 of C68) and the frame ground. Does the test lamp illuminate?

Refer to "LHD Body Control" in the ETM (wiring diagram). (Open using the ETM viewer.).

Refer to "RHD Body Control (4JJ3 with DPD)" in the ETM (wiring diagram). (Open using the ETM viewer.).

Refer to "RHD Body Control (4JJ3 without DPD, RZ4E)" in the ETM (wiring diagram). (Open using the ETM viewer.).

Yes

=>Go to Inspection for open circuit in stop light switch signal circuit.

No

Repair the open circuit or high resistance in the circuit between the STOP 10A fuse and the stop light switch (pin 1 of C68).

=>Go to Repair verification.

7. Inspection for open circuit in stop light switch signal circuit

1) Inspect the circuit between the BCM (pin 20 of C17) and the stop light switch (pin 2 of C68) for an open circuit or high resistance. Is the result normal?

Refer to "LHD Body Control" in the ETM (wiring diagram). (Open using the ETM viewer.).

Refer to "RHD Body Control (4JJ3 with DPD)" in the ETM (wiring diagram). (Open using the ETM viewer.).

Refer to "RHD Body Control (4JJ3 without DPD, RZ4E)" in the ETM (wiring diagram). (Open using the ETM viewer.).

Yes

=>Go to BCM harness connector inspection.

No

Repair the circuit as necessary.

=>Go to Repair verification.

8. Inspection for short to power supply in stop light switch signal circuit

1) Inspect the circuit between the BCM (pin 20 of C17) and the stop light switch (pin 2 of C68) for a short to the battery power supply circuit or a short to the ignition power supply circuit. Is the result normal?

Refer to "LHD Body Control" in the ETM (wiring diagram). (Open using the ETM viewer.).

Refer to "RHD Body Control (4JJ3 with DPD)" in the ETM (wiring diagram). (Open using the ETM viewer.).

Refer to "RHD Body Control (4JJ3 without DPD, RZ4E)" in the ETM (wiring diagram). (Open using the ETM viewer.).

Yes

=>Go to BCM replacement.

No

Repair the circuit as necessary.

=>Go to Repair verification.

9. BCM harness connector inspection

1) Inspect for poor connections at the BCM harness connector (pin 20 of C17). Is the connection status normal?

Refer to "LHD Body Control" in the ETM (wiring diagram). (Open using the ETM viewer.).

Refer to "RHD Body Control (4JJ3 with DPD)" in the ETM (wiring diagram). (Open using the ETM viewer.).

Refer to "RHD Body Control (4JJ3 without DPD, RZ4E)" in the ETM (wiring diagram). (Open using the ETM viewer.).

Yes

=>Go to BCM replacement.

No

Repair the connections as necessary.

=>Go to Repair verification.

10. BCM replacement

Refer to "9.Body, Cab, Accessories 9Z.Body, Cab, Accessories Electrical Control BCM removal".

Refer to "9.Body, Cab, Accessories 9Z.Body, Cab, Accessories Electrical Control BCM installation".

Refer to "9.Body, Cab, Accessories 9Z.Body, Cab, Accessories Electrical Control BCM setting".

Procedure completion

=>Go to Repair verification.

11. Repair verification

1) Connect all of the disconnected harness connectors.

2) Connect the scan tool.

3) Turn ON the ignition switch.

4) Observe the Brake Lamp Switch (M02-20) parameter while depressing and releasing the brake pedal repeatedly. Does the Brake Lamp Switch (M02-20) parameter match the brake pedal operation?

Yes

The system is normal.

No

=>Go to Stop light switch signal check.