Inspection Procedure

NOTE: When replacing the brake actuator assembly, perform zero point calibration (See CALIBRATION ).

HINT:

When C1425 is output together with C1380, inspect and repair the trouble areas indicated by C1425 first (See DTC C1425 OPEN IN STOP LIGHT SWITCH CIRCUIT ).

CHECK STOP LIGHT OPERATION

Check that the stop lights come on when the brake pedal is depressed, and go off when the brake pedal is released.

ILLUMINATION CONDITION CHART

Condition	Illumination Condition
Brake pedal depressed.	ON
Brake pedal released.	OFF

NG : INSPECT STOP LIGHT CIRCUIT (See STOP LIGHT SWITCH CIRCUIT )

OK : Go to Next Step

READ VALUE USING TECHSTREAM (STOP LIGHT SWITCH)

Connect the Techstream to the DLC3.
Turn the ignition switch to ON.

Select the Data List mode on the Techstream (See DATA LIST / ACTIVE TEST ).

ABS/VSC/TRAC:

ABS/VSC/TRAC REFERENCE CHART

Tester Display	Measurement Item/Range	Normal Condition	Diagnostic Note
Stop Light SW	Stop light switch / ON or OFF	ON: Brake pedal depressed OFF: Brake pedal released	-

Check that the stop light switch condition observed on the Techstream changes according to brake pedal operation.
OK: The Techstream displays ON or OFF according to brake pedal operation.

NG : Go to step 9

OK : Go to Next Step

INSPECT SKID CONTROL ECU (STP TERMINAL)

Turn the ignition switch off.
Make sure that there is no looseness in the locking part and connecting part of the connector.
Disconnect the skid control ECU connector.
Measure the voltage according to the value(s) in the table below.

Standard Voltage

TESTER CONNECTION SPECIFIED CONDITION CHART

Tester Connection	Switch Condition	Specified Condition
A19-2 (STP) - Body ground	Stop light switch off (Brake pedal released)	Below 1.5 V
A19-2 (STP) - Body ground	Stop light switch on (Brake pedal depressed)	8 to 14 V

NG : REPAIR OR REPLACE HARNESS OR CONNECTOR (STP CIRCUIT)

Fig 1: Identifying A19 Skid Control ECU Connector Terminals

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

OK : Go to Next Step

PERFORM ACTIVE TEST USING TECHSTREAM (STOP LIGHT RELAY)

Reconnect the skid control ECU connector.
Connect the Techstream to the DLC3.
Start the engine.

Select the Active Test mode on the Techstream (See DATA LIST / ACTIVE TEST ).

ABS/VSC/TRAC:

ABS/VSC/TRAC REFERENCE CHART

Tester Display	Test Part	Control Range	Diagnostic Note
Stop Light Relay	Stop light control relay (BRK)	Relay ON/OFF	Observe the stop lights.

Check that the "ON" and "OFF" of the stop lights can be shown on the rear combination light by the Techstream.

OK: The stop lights turn on or off in accordance with the Techstream.

NG : Go to step 6

OK : Go to Next Step

RECONFIRM DTC

Turn the ignition switch off.
Clear the DTCs (See DTC CHECK / CLEAR ).
Start the engine.
Perform a road test.
Check if the same DTC is output (See DTC CHECK / CLEAR ).

Result

RESULT CHART

Result	Proceed to
DTC (C1380) is not output.	A
DTC (C1380) is output.	B

B : REPLACE BRAKE ACTUATOR ASSEMBLY (See REMOVAL )

A : CHECK FOR INTERMITTENT PROBLEMS (SYMPTOM SIMULATION) (See HOW TO PROCEED WITH TROUBLESHOOTING )

INSPECT STOP LIGHT CONTROL RELAY (BRK)

Turn the ignition switch off.
Remove the stop light control relay (BRK).
Measure the resistance according to the value(s) in the table below.

Standard Resistance

TESTER CONNECTION SPECIFIED CONDITION CHART

Tester Connection	Condition	Specified Condition
3 - 4	Voltage is not applied between terminals 1 and 2	Below 1 Ω
3 - 5	Voltage is not applied between terminals 1 and 2	10 kΩ or higher
3 - 4	Voltage is applied between terminals 1 and 2	10 kΩ or higher
3 - 5	Voltage is applied between terminals 1 and 2	Below 1 Ω

Fig 2: Stop Light Control Relay Circuit Diagram

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

NG : REPLACE STOP LIGHT CONTROL RELAY (BRK)

OK : Go to Next Step

INSPECT ENGINE ROOM NO. 1 RELAY BLOCK (POWER SOURCE TERMINAL)

Measure the voltage according to the value(s) in the table below.

Standard Voltage

TESTER CONNECTION SPECIFIED CONDITION CHART

Tester Connection	Switch Condition	Specified Condition
Stop light control relay (BRK) terminal 5 - Body ground	Always	11 to 14 V
Stop light control relay (BRK) terminal 2 - Body ground	Ignition switch ON	11 to 14 V

NG : REPAIR OR REPLACE HARNESS OR CONNECTOR (POWER SOURCE CIRCUIT)

Fig 3: Identifying Engine Room No. 1 Relay Block Connector Terminals

OK : Go to Next Step

INSPECT SKID CONTROL ECU (STPO TERMINAL)

Install the stop light control relay (BRK).
Make sure that there is no looseness in the locking part and connecting part of the connector.
Disconnect the skid control ECU connector.
Turn the ignition switch to ON.
Measure the voltage according to the value(s) in the table below.

Standard Voltage

TESTER CONNECTION SPECIFIED CONDITION CHART

Tester Connection	Switch Condition	Specified Condition
A19-31 (STPO) - Body ground	Ignition switch ON	11 to 14 V

NG : REPAIR OR REPLACE HARNESS OR CONNECTOR (STPO CIRCUIT)

Fig 4: Identifying A19 Skid Control ECU Connector Terminals (STPO)

OK : REPLACE BRAKE ACTUATOR ASSEMBLY (See REMOVAL )

INSPECT SKID CONTROL ECU (STP2 TERMINAL)

Turn the ignition switch off.
Make sure that there is no looseness in the locking part and connecting part of the connector.
Disconnect the skid control ECU connector.
Measure the voltage according to the value(s) in the table below.

Standard Voltage

TESTER CONNECTION SPECIFIED CONDITION CHART

Tester Connection	Switch Condition	Specified Condition
A19-22 (STP2) - Body ground	Stop light switch on (Brake pedal depressed)	8 to 14 V
A19-22 (STP2) - Body ground	Stop light switch off (Brake pedal released)	Below 1.5 V

NG : REPAIR OR REPLACE HARNESS OR CONNECTOR (STP2 CIRCUIT)

Fig 5: Identifying A19 Skid Control ECU Connector Terminals (STP2)

OK : REPLACE BRAKE ACTUATOR ASSEMBLY (See REMOVAL )