DTC B1719[12] Rear Defogger Output Circuit Short to Battery (BCM)

1. Body control system check

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

2. Current DTC check

1) Connect the scan tool.

2) Turn OFF the ignition switch.

3) Turn ON the ignition switch.

4) Observe the DTC information with a scan tool. Is a DTC set?

Yes

=>Go to Rear defogger relay inspection.

No

Go to Intermittent conditions of body control system.

Refer to "223.Body Control 36D.Symptom(BCM) intermittent conditions of body control system".

3. Rear defogger relay inspection

1) Clear the DTC with a scan tool.

2) Turn OFF the ignition switch.

3) Remove the rear defogger relay.

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.).

4) Turn ON the ignition switch.

5) Observe the DTC information with a scan tool. Is a DTC set?

Yes

=>Go to Electronic device connection check to rear defogger relay drive circuit.

No

Replace the rear defogger relay.

=>Go to Repair verification.

4. Electronic device connection check to rear defogger relay drive circuit

1) Check whether no aftermarket electronics are connected to the rear defogger relay drive circuit. Are any aftermarket electronics connected?

Yes

Remove the aftermarket electronics.

=>Go to Repair verification.

No

=>Go to Inspection for short to power supply in rear defogger relay drive circuit.

5. Inspection for short to power supply in rear defogger relay drive circuit

1) Disconnect the BCM harness connector (B18).

2) Inspect the relay drive circuit between the BCM (pin 16 of B18) and the rear defogger relay (pin 9 of B1) 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.

6. 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.

7. Repair verification

1) Clear the DTC with a scan tool.

2) Turn OFF the ignition switch for 30 seconds or more.

3) Turn ON the ignition switch.

4) Observe the DTC information with a scan tool.