DTC C1126:13 [BCM]


id0902f5940200

DESCRIPTION

TNS switch circuit malfunction

DETECTION CONDITION
•  Open circuit in the TNS switch circuit with the TNS switch on.
POSSIBLE CAUSE
•  Light switch connector or terminals malfunction
•  Open circuit in wiring harness between the following terminals:
―  Light switch terminal E—Body ground
•  Light switch malfunction
•  BCM connector or terminals malfunction
•  Open circuit in wiring harness between the following terminals:
―  Light switch terminal A—BCM terminal 2V
•  BCM malfunction

Diagnostic Procedure

STEP

INSPECTION

ACTION

1
CONFIRM BCM DTC
•  Clear the DTC using the M-MDS.
•  Perform the BCM DTC inspection using the M-MDS with the TNS switch on.
•  Is the same DTC present?
Yes
Go to the next step.
No
Go to Step 9.
2
INSPECT LIGHT SWITCH CONNECTOR AND TERMINALS
•  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 8.
No
Go to the next step.
3
VERIFY MALFUNCTIONING LOCATION
•  Light switch connector is disconnected.
•  Reconnect the negative battery cable.
•  Switch the ignition to ON.
•  Measure the voltage at the following terminal (wiring harness-side):
―  Light switch terminal A
•  Is there any voltage?
Yes
Go to the next step.
No
Go to Step 6.
4
INSPECT TNS SWITCH CIRCUIT FOR OPEN CIRCUIT
•  Light switch connector is disconnected.
•  Switch the ignition to off.
•  Disconnect the negative battery cable.
•  Inspect for continuity between the following terminal (wiring harness-side) and body ground:
―  Light switch terminal E
•  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 8.
5
INSPECT LIGHT SWITCH
•  Inspect the light switch.
•  Is there any malfunction?
Yes
Replace the light switch, then go to Step 8.
No
Go to Step 8.
6
INSPECT BCM CONNECTOR AND TERMINALS
•  Switch the ignition to off.
•  Disconnect the negative battery cable.
•  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 8.
No
Go to the next step.
7
INSPECT TNS SWITCH CIRCUIT FOR OPEN CIRCUIT
•  Light switch and BCM connectors are disconnected.
•  Reconnect the BCM connector.
•  Reconnect the negative battery cable.
•  Measure the voltage at the following terminal (wiring harness-side):
―  BCM terminal 2V
•  Is there any voltage?
Yes
Repair or replace the wiring harness for a possible open circuit, then go to the next step.
No
Go to the next step.
8
VERIFY TROUBLESHOOTING COMPLETED
•  Make sure to reconnect the disconnected connectors.
•  Reconnect the negative battery cable.
•  Clear the DTC using the M-MDS.
•  Perform the BCM DTC inspection using the M-MDS with the TNS switch on.
•  Is the same DTC present?
Yes
Replace the BCM, then go to the next step.
No
Go to the next step.
9
VERIFY THAT NO OTHER DTCs ARE PRESENT
•  Are any DTCs present?
Yes
Go to the applicable DTC inspection.
No
DTC troubleshooting completed.