DTC C1726[13] Right Head Light (Low Beam) Output Circuit Open (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) Operate the light control switch to the low beam position.

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

Yes

=>Go to Headlight inspection.

Go to Intermittent conditions of body control system.

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

3. Headlight inspection

1) Inspect the headlight for the following. Is the result normal?

Whether the headlight (right) bulb is burnt out
Whether there is any improper installation
Whether there is any rust or corrosion on the contact point

Yes

=>Go to Inspection for open circuit in headlight (right) low beam output circuit.

Repair or replace as necessary.

=>Go to Repair verification.

4. Inspection for open circuit in headlight (right) low beam output circuit

1) Disconnect the following harness connector.

BCM harness connector (C18)
Headlight (right) harness connector (C28 for models with LED headlights, C30 for models with halogen headlights)

2) Inspect the headlight (right) low beam output circuit between the BCM (pin 7 of C18) and the headlight (pin 1 of C28 or pin 2 of C30) 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 Inspection for open circuit in headlight (right) low beam ground circuit.

Repair the circuit as necessary.

=>Go to Repair verification.

5. Inspection for open circuit in headlight (right) low beam ground circuit

1) Inspect the ground circuit between the headlight (pin 3 of C28 or pin 4 of C30) and the body ground 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.

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 7 of C18). 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.

Repair the connections as necessary.

=>Go to Repair verification.

7. BCM replacement

Note

Perform programming after replacing the BCM.

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) Operate the light control switch to the low beam position.

5) Observe the DTC information with a scan tool.