Toyota Tundra Service Manual: Stop Light Control Relay Malfunction (C1380)

DESCRIPTION

The skid control ECU (brake actuator assembly) sends a stop light operation request signal to the stop light control relay. If the skid control ECU (brake actuator assembly) detects a malfunction in the stop light control relay circuit, the trailer brake control ECU (brake control with bracket relay) stores DTC C1380.

DTC No.

Detection Item

INF Code

DTC Detection Condition

Trouble Area

C1380

Stop Light Control Relay Malfunction

-

While the ignition switch is ON, the trailer brake control ECU (brake control with bracket relay) receives a stop light control relay circuit malfunction signal from the skid control ECU (brake actuator assembly) for 2 seconds or more.

  • Vehicle stability control system
  • Trailer brake control ECU (brake control with bracket relay)

CAUTION / NOTICE / HINT

NOTICE:

The trailer brake control system uses the CAN communication system. First, confirm that there are no malfunctions in the CAN communication system. Refer to How to Proceed with Troubleshooting.

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PROCEDURE

1.

CHECK FOR DTCs (VEHICLE STABILITY CONTROL SYSTEM)

HINT:

Trailer brake control system DTC C1380 may be stored due to a malfunction in the vehicle stability control system. Therefore, it is necessary to check for and troubleshoot vehicle stability control system DTCs first.

(a) Check for DTCs.

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Result

Proceed to

Vehicle stability control system DTCs are not output

A

Vehicle stability control system DTCs are output

B

B

GO TO VEHICLE STABILITY CONTROL SYSTEM

A

2.

CHECK FOR DTCs (TRAILER BRAKE CONTROL SYSTEM)

(a) Clear the DTCs.

Click here

(b) Turn the ignition switch off.

(c) Turn the ignition switch to ON.

(d) Check if the same DTC is output.

Click here

Result

Proceed to

DTCs C1380 is not output.

A

DTCs C1380 is output.

B

A

USE SIMULATION METHOD TO CHECK

B

REPLACE BRAKE CONTROL WITH BRACKET RELAY

    Acceleration Sensor Output Malfunction (C1245)

    Data List / Active Test

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