DTC C1126:13 [BCM]

id0902f5940200

Description

• Light switch (TNS) circuit malfunction

Detection Condition

• Open circuit in light switch (TNS) circuit with the light switch at TNS position.

Possible Causes

• Light switch connector or terminals malfunction

• Open circuit in wiring harness between the following:

― Light switch terminal B—Body ground (Vehicles with light switch on left side)

― Light switch terminal N—Body ground (Vehicles with light switch on right side)

• Light switch malfunction

• BCM connector or terminals malfunction

• Open circuit in wiring harness between the following terminals:

― Light switch terminal D—BCM terminal 3O (Vehicles with light switch on left side)

― Light switch terminal L—BCM terminal 3O (Vehicles with light switch on right side)

• BCM malfunction

System Wiring Diagram

am6zzw00006968

Diagnostic Procedure

Step

Inspection

Action

1

PERFORM DTC INSPECTION

•  Clear the DTCs using the M-MDS.
(See CLEARING DTC [BCM].)

•  Perform the BCM DTC inspection using the M-MDS.
(See DTC INSPECTION [BCM].)

•  Is the DTC C1126:13 present?

Yes

Go to the next step.

No

DTC troubleshooting completed.

2

INSPECT LIGHT SWITCH CONNECTOR CONDITION

•  Switch the ignition to off.

•  Disconnect the negative battery cable.

•  Disconnect the light switch connector.

•  Inspect the connector and terminals (corrosion, damage, pin disconnection).

•  Is there any malfunction?

Yes

Repair or replace the connector or terminals, then go to Step 7.

No

Go to the next step.

3

INSPECT LIGHT SWITCH GROUND CIRCUIT FOR OPEN CIRCUIT

•  Light switch connector is disconnected.

•  Inspect for continuity between the following terminal (wiring harness-side) and body ground:

―  Light switch terminal B (Vehicles with light switch on left side)

―  Light switch terminal N (Vehicles with light switch on right side)

•  Is there continuity?

Yes

Go to the next step.

No

Repair or replace the wiring harness for a possible open circuit, then go to Step 7.

4

INSPECT LIGHT SWITCH

•  Inspect the light switch.
(See LIGHT SWITCH INSPECTION.)

•  Is there any malfunction?

Yes

Replace the light switch, then go to Step 7.

(See LIGHT SWITCH REMOVAL/INSTALLATION.)

No

Go to the next step.

5

INSPECT BCM CONNECTOR CONDITION

•  Disconnect the BCM connector.

•  Inspect the connector and terminals (corrosion, damage, pin disconnection).

•  Is there any malfunction?

Yes

Repair or replace the connector or terminals, then go to Step 7.

No

Go to the next step.

6

INSPECT LIGHT SWITCH POWER SUPPLY CIRCUIT FOR OPEN CIRCUIT

•  Make sure to reconnect all disconnected connectors.

•  Reconnect the negative battery cable.

•  Measure the voltage at the BCM terminal 3O (wiring harness-side).

•  Can the voltage be measured?

Yes

Repair or replace the wiring harness for a possible open circuit, then go to the next step.

No

Go to the next step.

7

VERIFY TROUBLESHOOTING COMPLETED

•  Make sure to reconnect all disconnected connectors.

•  Reconnect the negative battery cable.

•  Clear the DTCs using the M-MDS.
(See CLEARING DTC [BCM].)

•  Perform the BCM DTC inspection using the M-MDS.
(See DTC INSPECTION [BCM].)

•  Is the DTC C1126:13 present?

Yes

Repeat the inspection from Step 1.

•  If the malfunction recurs, replace the BCM.
(See BODY CONTROL MODULE (BCM) REMOVAL/INSTALLATION.)

Go to the next step.

No

Go to the next step.

8

VERIFY THAT NO OTHER DTCs ARE PRESENT

•  Are any DTCs present?

Yes

Go to the applicable DTC inspection.

(See DTC TABLE [BCM].)

No

DTC troubleshooting completed.

Step	Inspection		Action
1	PERFORM DTC INSPECTION • Clear the DTCs using the M-MDS. (See CLEARING DTC [BCM].) • Perform the BCM DTC inspection using the M-MDS. (See DTC INSPECTION [BCM].) • Is the DTC C1126:13 present?	Yes	Go to the next step.
1		No	DTC troubleshooting completed.
2	INSPECT LIGHT SWITCH CONNECTOR CONDITION • Switch the ignition to off. • Disconnect the negative battery cable. • Disconnect the light switch connector. • Inspect the connector and terminals (corrosion, damage, pin disconnection). • Is there any malfunction?	Yes	Repair or replace the connector or terminals, then go to Step 7.
2		No	Go to the next step.
3	INSPECT LIGHT SWITCH GROUND CIRCUIT FOR OPEN CIRCUIT • Light switch connector is disconnected. • Inspect for continuity between the following terminal (wiring harness-side) and body ground: ― Light switch terminal B (Vehicles with light switch on left side) ― Light switch terminal N (Vehicles with light switch on right side) • Is there continuity?	Yes	Go to the next step.
3		No	Repair or replace the wiring harness for a possible open circuit, then go to Step 7.
4	INSPECT LIGHT SWITCH • Inspect the light switch. (See LIGHT SWITCH INSPECTION.) • Is there any malfunction?	Yes	Replace the light switch, then go to Step 7. (See LIGHT SWITCH REMOVAL/INSTALLATION.)
4		No	Go to the next step.
5	INSPECT BCM CONNECTOR CONDITION • Disconnect the BCM connector. • Inspect the connector and terminals (corrosion, damage, pin disconnection). • Is there any malfunction?	Yes	Repair or replace the connector or terminals, then go to Step 7.
5		No	Go to the next step.
6	INSPECT LIGHT SWITCH POWER SUPPLY CIRCUIT FOR OPEN CIRCUIT • Make sure to reconnect all disconnected connectors. • Reconnect the negative battery cable. • Measure the voltage at the BCM terminal 3O (wiring harness-side). • Can the voltage be measured?	Yes	Repair or replace the wiring harness for a possible open circuit, then go to the next step.
6		No	Go to the next step.
7	VERIFY TROUBLESHOOTING COMPLETED • Make sure to reconnect all disconnected connectors. • Reconnect the negative battery cable. • Clear the DTCs using the M-MDS. (See CLEARING DTC [BCM].) • Perform the BCM DTC inspection using the M-MDS. (See DTC INSPECTION [BCM].) • Is the DTC C1126:13 present?	Yes	Repeat the inspection from Step 1. • If the malfunction recurs, replace the BCM. (See BODY CONTROL MODULE (BCM) REMOVAL/INSTALLATION.) Go to the next step.
7		No	Go to the next step.
8	VERIFY THAT NO OTHER DTCs ARE PRESENT • Are any DTCs present?	Yes	Go to the applicable DTC inspection. (See DTC TABLE [BCM].)
8		No	DTC troubleshooting completed.