Diagnosis Procedure
- CHECK DTC PRIORITY
If DTC P1572 is displayed with DTC P0605, first perform the confirmation procedure for DTC P0605.
Is applicable DTC detected?
YES
Perform diagnosis of applicable. Refer to DTC Description .
NO
GO TO 2.
- CHECK OVERALL FUNCTION-I
With CONSULT
- Turn ignition switch ON.
- Select "BRAKE SW1" in "DATA MONITOR" mode with CONSULT.
- Check "BRAKE SW1" indication under the following conditions.
Monitor item
Condition
Indication
BRAKE SW1
(ICC brake switch)
Brake pedal
Slightly depressed
OFF
Brake pedal
Fully released
ON
Without CONSULT
- Turn ignition switch ON.
- Check the voltage between ECM harness connector terminals under the following conditions.
ECM
Condition
Voltage (V)
Connector
+
-
Terminal
Terminal
E10
140
152
Brake pedal
Slightly depressed
Approx. 0
Brake pedal
Fully released
Battery voltage
Is the inspection result normal?
YES
GO TO 3.
NO
GO TO 4.
- CHECK OVERALL FUNCTION-II
Select "BRAKE SW2" and check indication under the following conditions.
Monitor item
Condition
Indication
BRAKE SW2
(Stop lamp switch)
Brake pedal
Slightly depressed
ON
Fully released
OFF
Check the voltage between ECM harness connector terminals as per the following.
ECM
Condition
Voltage (V)
Connector
+
-
Terminal
Terminal
E10
139
152
Brake pedal
Slightly depressed
Battery voltage
Fully released
Approx. 0
Is the inspection result normal?
YES
INSPECTION END
NO
GO TO 7.
- CHECK BRAKE PEDAL POSITION SWITCH POWER SUPPLY
- Turn ignition switch OFF.
- Disconnect brake pedal position switch harness connector.
- Turn ignition switch ON.
- Check the voltage between brake pedal position switch harness connector and ground.
+
-
Voltage
Brake pedal position switch
Connector
Terminal
E37
1
Ground
Battery voltage
Is the inspection result normal?
YES
GO TO 5.
NO
Perform the trouble diagnosis for power supply circuit.
- CHECK BRAKE PEDAL POSITION SWITCH INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
- Turn ignition switch OFF.
- Disconnect ECM harness connector.
- Check the continuity between brake pedal position switch harness connector and ECM harness connector.
Brake pedal position switch
ECM
Continuity
Connector
Terminal
Connector
Terminal
E37
2
E10
140
Existed
- Also check harness for short to ground and short to power.
Is the inspection result normal?
YES
GO TO 6.
NO
Repair or replace error-detected parts.
- CHECK BRAKE PEDAL POSITION SWITCH
Check brake pedal position switch. Refer to Component Inspection (ICC Brake Switch) .
Is the inspection result normal?
YES
INSPECTION END
NO
Replace brake pedal position switch. Refer to Removal and Installation .
- CHECK STOP LAMP RELAY POWER SUPPLY CIRCUIT
- Turn ignition switch OFF.
- Disconnect stop lamp relay harness connector.
- Check the voltage between stop lamp relay harness connector and ground.
+
-
Voltage
Stop lamp relay
Connector
Terminal
E34
1
Ground
Battery voltage
Is the inspection result normal?
YES
GO TO 8.
NO
Perform the trouble diagnosis for power supply circuit.
- CHECK STOP LAMP SWITCH POWER SUPPLY CIRCUIT-I
- Reconnect stop lamp relay harness connector.
- Disconnect stop lamp switch harness connector.
- Check the voltage between stop lamp switch harness connector and ground.
+
-
Voltage
Stop lamp switch
Connector
Terminal
E38
2
Ground
Battery voltage
Is the inspection result normal?
YES
GO TO 10.
NO
GO TO 9.
- CHECK STOP LAMP SWITCH POWER SUPPLY CIRCUIT-II
- Disconnect stop lamp relay harness connector.
- Check the continuity between stop lamp switch harness connector and stop lamp relay harness connector.
+
-
Continuity
Stop lamp switch
Stop lamp relay
Connector
Terminal
Connector
Terminal
E38
2
E34
2
Existed
- Also check harness for short to ground and to power.
Is the inspection result normal?
YES
INSPECTION END
NO
Repair or replace error-detected parts.
- CHECK STOP LAMP SWITCH GROUND CIRCUIT
Check the continuity between stop lamp switch harness connector and ground.
+
-
Continuity
Stop lamp switch
Connector
Terminal
E38
1
Ground
Existed
Is the inspection result normal?
YES
GO TO 11.
NO
Perform the trouble diagnosis for power supply circuit.
- CHECK STOP LAMP SWITCH
Check the stop lamp switch. Refer to Component Inspection (Stop Lamp Switch) .
Is the inspection result normal?
YES
GO TO 12.
NO
Replace stop lamp switch. Refer to Exploded View .
- CHECK STOP LAMP SWITCH SIGNAL POWER SUPPLY
Check the voltage between stop lamp relay harness connector and ground.
+
-
Voltage
Stop lamp relay
Connector
Terminal
E34
3
Ground
Battery voltage
Is the inspection result normal?
YES
GO TO 13.
NO
Perform the trouble diagnosis for power supply circuit.
- CHECK STOP LAMP SWITCH SIGNAL CIRCUIT
- Disconnect ECM harness connector.
- Check the continuity between stop lamp relay harness connector and ECM harness connector.
+
-
Continuity
Stop lamp relay
ECM
Connector
Terminal
Connector
Terminal
E34
5
E10
139
Existed
- Also check harness for short to ground and to power.
Is the inspection result normal?
YES
GO TO 14.
NO
Repair or replace error-detected parts
- CHECK STOP LAMP RELAY
Check the stop lamp relay. Refer to Component Inspection (Stop Lamp Relay) .
Is the inspection result normal?
YES
Check ICC brake hold relay circuit. Refer to Diagnosis Procedure .
NO
Replace stop lamp relay.