C1380

BRAKE CONTROL: VEHICLE STABILITY CONTROL SYSTEM: C1380/64: Stop Light Control Relay Malfunction

DTC C1380/64 - Stop Light Control Relay Malfunction

DESCRIPTION

Upon receiving the downhill assist control or hill-start assist control operating signal from the skid control ECU, the relay contact turns on and the stop light comes on.





WIRING DIAGRAM





INSPECTION PROCEDURE

NOTE: When replacing the master cylinder solenoid, perform zero point calibration Programming and Relearning.

PROCEDURE

1. CHECK STOP LIGHT SWITCH OPERATION
(a) Check that the stop light comes on when the brake pedal is depressed, and goes off when the brake pedal is released.
OK:
Stop light switch function is normal.

HINT: Check the stop light bulb as it may have burnt out.

NG -- INSPECT STOP LIGHT SWITCH ASSEMBLY (POWER SOURCE TERMINAL)
OK -- Continue to next step.

2. INSPECT SKID CONTROL ECU (STP TERMINAL)




(a) Disconnect the skid control ECU connector.
(b) Measure the voltage according to the value(s) in the table below.
Standard voltage:





NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR (STP CIRCUIT)
OK -- Continue to next step.

3. INSPECT SKID CONTROL ECU (STP2 TERMINAL)




(a) Measure the resistance according to the value(s) in the table below.
Standard resistance:





NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR (STP2 CIRCUIT)
OK -- Continue to next step.

4. PERFORM ACTIVE TEST USING TECHSTREAM (STOP LIGHT OPERATION RELAY)
(a) Reconnect the skid control ECU connector.
(b) Connect Techstream to the DLC3.
(c) Turn the ignition switch to ON and turn the Techstream main switch ON.
(d) Select "Active Test" mode on Techstream.

ABS/VSC/TRAC





(e) Check that the stop light in the rear combination light turns on and off when the stop light operation relay is turned on and off using Techstream.
OK:
The stop light turns on or off in accordance with Techstream.
OK -- RECONFIRM DTC

NG -- Continue to next step.

5. INSPECT STOP LIGHT OPERATION RELAY (POWER SOURCE TERMINAL)




(a) Remove the stop light operation relay.
(b) Turn the ignition switch to ON.
(c) Measure the voltage according to the value(s) in the table below.
Standard voltage:





NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR (POWER SOURCE CIRCUIT)
OK -- Continue to next step.

6. INSPECT STOP LIGHT OPERATION RELAY




(a) Measure the resistance according to the value(s) in the table below.
Standard resistance:





NG -- REPLACE STOP LIGHT OPERATION RELAY
OK -- Continue to next step.

7. INSPECT SKID CONTROL ECU (STPO TERMINAL)




(a) Install the stop light operation relay.
(b) Disconnect the skid control ECU connector.
(c) Turn the ignition switch to ON.
(d) Measure the voltage according to the value(s) in the table below.
Standard voltage:





NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR (STPO CIRCUIT)
OK -- Continue to next step.

8. RECONFIRM DTC C1242
B -- CHECK FOR INTERMITTENT PROBLEMS
A -- REPLACE MASTER CYLINDER SOLENOID
9. INSPECT STOP LIGHT SWITCH ASSEMBLY (POWER SOURCE TERMINAL)




(a) Disconnect the stop light switch connector.
(b) Measure the voltage according to the value(s) in the table below.
Standard voltage:

w/o Rear Spoiler





w/ Rear Spoiler





NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR (POWER SOURCE CIRCUIT)
OK -- Continue to next step.

10. INSPECT STOP LIGHT SWITCH ASSEMBLY




(a) Measure the resistance according to the value(s) in the table below.
Standard resistance:





NG -- REPLACE STOP LIGHT SWITCH ASSEMBLY
OK -- Continue to next step.

11. CHECK HARNESS AND CONNECTOR (STOP LIGHT SWITCH - STOP LIGHT OPERATION RELAY)




(a) Remove the stop light operation relay.
(b) Measure the resistance according to the value(s) in the table below.
Standard resistance:

w/o Rear Spoiler





w/ Rear Spoiler





NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- Continue to next step.

12. INSPECT STOP LIGHT OPERATION RELAY




(a) Measure the resistance according to the value(s) in the table below.
Standard resistance:





NG -- REPLACE STOP LIGHT OPERATION RELAY
OK -- Continue to next step.

13. CHECK HARNESS AND CONNECTOR (REAR COMBINATION LIGHT - RELAY AND BODY GROUND)




(a) Disconnect the rear combination light connector.
(b) Measure the resistance according to the value(s) in the table below.
Standard resistance:
for LH





for RH:





NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- REPLACE MASTER CYLINDER SOLENOID