DTC C1706[14] Rear Fog Lamp Output Circuit Open or Short to Ground (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) Turn ON the head light and operate the fog light switch to the rear position.

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

Yes

=>Go to Rear fog light 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 fog light relay inspection

1) Remove the rear fog light 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.).

2) Inspect the relay. Is the relay normal?

Yes

=>Go to Inspection for short to ground in rear fog light relay drive circuit.

No

Replace the rear fog light relay.

=>Go to Repair verification.

4. Inspection for short to ground in rear fog light relay drive circuit

1) Turn OFF the ignition switch.

2) Disconnect the BCM harness connector (C17).

3) Connect a test lamp between the BCM (pin 23 of C17) and the battery power supply. 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

Repair the short to ground in the relay drive circuit between the BCM (pin 23 of C17) and the rear fog light relay (pin 4 of R7 RR FOG).

=>Go to Repair verification.

No

=>Go to Inspection for open circuit in rear fog light relay drive circuit.

5. Inspection for open circuit in rear fog light relay drive circuit

1) Inspect the relay drive circuit between the BCM (pin 23 of C17) and the rear fog light relay (pin 4 of R7 RR FOG) 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.

6. BCM harness connector inspection

1) Inspect for poor connections at the BCM harness connector (pin 23 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.

7. 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.

8. 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) Turn ON the head light and operate the fog light switch to the rear position.

5) Observe the DTC information with a scan tool.