C1380

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

DTC C1380/64 - Stop Light Control Relay Malfunction

DESCRIPTION

The skid control ECU inputs the stop light switch signal and detects the status of the brake operation.

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 lights come on when the brake pedal is depressed and go off when the brake pedal is released.
OK:

HINT: Check the stop light bulbs as they may have burnt out.

NG -- CHECK STOP LIGHT SWITCH ASSEMBLY (STOP LIGHT SWITCH POWER SOURCE TERMINAL VOLTAGE)
OK -- Continue to next step.
2. INSPECT SKID CONTROL ECU (STP TERMINAL VOLTAGE)

(a) Disconnect the skid control ECU connector.
(b) Measure the voltage.
Standard Voltage:

(c) Reconnect the skid control ECU connector.
NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR (STP CIRCUIT)
OK -- Continue to next step.
3. INSPECT SKID CONTROL ECU (STP2 TERMINAL VOLTAGE)

(a) Disconnect the skid control ECU connector.
(b) Measure the resistance.
Standard Resistance:

(c) Reconnect the skid control ECU connector.
NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR (STP2 CIRCUIT)
OK -- Continue to next step.
4. PERFORM ACTIVE TEST USING TECHSTREAM (STOP LIGHT RELAY)
(a) Connect Techstream to the DLC3.
(b) Turn the ignition switch to the ON position.
(c) Turn Techstream ON.
(d) Select the Active Test mode on Techstream.

ABS/VSC/TRAC

(e) Check that the stop lights turn on and off on the rear combination light when using Techstream.
OK:
The stop lights turn on and off according to Techstream operations.
NG -- CHECK STOP LIGHT CONTROL RELAY
OK -- Continue to next step.
5. RECONFIRM DTC
(a) Clear the DTCs (Reading and Clearing Diagnostic Trouble Codes).
(b) Check if the same DTCs are recorded.

B -- END
A -- REPLACE MASTER CYLINDER SOLENOID
6. CHECK STOP LIGHT CONTROL RELAY

(a) Disconnect the STOP LP CTRL relay.
(b) Turn the ignition switch to the ON position.
(c) Measure the voltage.
Standard Voltage:

(d) Turn the ignition switch to OFF.
(e) Reconnect the STOP LP CTRL relay.
NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR (STOP LP CTRL RELAY)
OK -- Continue to next step.
7. INSPECT STOP LIGHT CONTROL RELAY

(a) Remove the STOP LP CTRL relay from the engine room R/B and J/B.
(b) Measure the resistance.
Standard Resistance:

(e) Reinstall the STOP LP CTRL relay.
NG -- REPLACE STOP LIGHT CONTROL RELAY
OK -- Continue to next step.
8. INSPECT MASTER CYLINDER SOLENOID (STPO TERMINAL VOLTAGE)

(a) Disconnect the skid control ECU connector.
(b) Turn the ignition switch to the ON position.
(c) Measure the voltage.
Standard Voltage:

(d) Turn the ignition switch to OFF.
(e) Reconnect the skid control ECU connector.
NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR (STOP CIRCUIT)
OK -- Continue to next step.
9. RECONFIRM DTC
(a) Clear the DTCs (Reading and Clearing Diagnostic Trouble Codes).
(b) Check if the same DTCs are recorded.

B -- END
A -- REPLACE MASTER CYLINDER SOLENOID
10. CHECK STOP LIGHT SWITCH ASSEMBLY (STOP LIGHT SWITCH POWER SOURCE TERMINAL VOLTAGE)

(a) Disconnect the stop light switch connector.
(b) Turn the ignition switch to the ON position.
(c) Measure the voltage.
Standard Voltage:

(d) Turn the ignition switch to OFF.
(e) Reconnect the stop light switch connector.
NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR (STOP LIGHT POWER SOURCE CIRCUIT)
OK -- Continue to next step.
11. INSPECT STOP LIGHT SWITCH ASSEMBLY

(a) Disconnect the stop light switch connector.
(b) Measure the resistance.
Standard Resistance:

(c) Reconnect the stop light switch connector.
NG -- REPLACE STOP LIGHT SWITCH ASSEMBLY
OK -- Continue to next step.
12. CHECK HARNESS AND CONNECTOR (STOP LIGHT SWITCH - STOP LP CTRL RELAY)

(a) Remove the STOP LP CTRL relay.
(b) Measure the resistance.
Standard Resistance:

(c) Reinstall the STOP LP CTRL relay.
NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- Continue to next step.
13. INSPECT STOP LIGHT CONTROL RELAY

(a) Remove the STOP LP CTRL relay from the engine room R/B and J/B.
(b) Measure the resistance.
Standard Resistance:

(e) Reinstall the STOP LP CTRL relay.
NG -- REPLACE STOP LIGHT CONTROL RELAY
OK -- Continue to next step.
14. CHECK HARNESS AND CONNECTOR (REAR COMBINATION LIGHT - STOP LP CTRL RELAY)

(a) Disconnect the rear combination light connector.
(b) Remove the STOP LP CTRL relay.
(c) Measure the resistance.
Standard Resistance (LH):

Standard Resistance (RH):

(d) Reinstall the STOP LP CTRL relay.
(e) Reconnect the rear combination light connector.
NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- CHECK FOR SHORTS IN ALL HARNESSES AND CONNECTORS CONNECTED TO FUSE AND REPLACE FUSE