Toyota Tundra. Manual — part 941

Fig. 79: Identifying A17 ECU And A18 Booster Connector Terminals
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

Standard Resistance

TESTER CONNECTION SPECIFIED CONDITION TABLE

NG: REPAIR OR REPLACE HARNESS OR CONNECTOR

OK: REPLACE VSC ACTUATOR ASSEMBLY (See REMOVAL )

DTC C1311/12: OPEN OR SHORT IN BRAKE INHIBIT RELAY CIRCUIT

DESCRIPTION

The stop light control relays are built into the stop light circuit and prohibits the stop light from turning on under
VSC control.

DTC DETECTION CONDITION TABLE

Tester Connection

Condition

Specified Condition

A17-17 (BST) - A18-3 (BST)

Always

Below 1 ohms

A17-17 (BST) - Body ground

Always

10 kohms or higher

A17-31 (BSTP) - A18-4 (BSTP)

Always

Below 1 ohms

A17-31 (BSTP) - Body ground

Always

10 kohms or higher

DTC Code

DTC Detection Condition

Trouble Area

2009 Toyota Tundra

2009 BRAKES Brake Control - Tundra

WIRING DIAGRAM

Refer to WIRING DIAGRAM .

INSPECTION PROCEDURE

1. CHECK TERMINAL VOLTAGE (STOP LIGHT CONTROL RELAY)

a. Remove the stop light control relays from the engine room relay block.

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

Standard Voltage

TESTER CONNECTION SPECIFIED CONDITION TABLE

C1311/12

Open or short circuit is detected.



Stop light control relay



Stop light control circuit

NOTE:

When replacing the VSC actuator assembly, perform the zero point calibration
(See CALIBRATION ).

Tester Connection

Switch Condition

Specified Condition

Stop light control relay terminal
1 (BRK NO. 1) - Body ground

Ignition switch ON

11 to 14 V

Stop light control relay terminal
1 (BRK NO. 2) - Body ground

2009 Toyota Tundra

2009 BRAKES Brake Control - Tundra

Fig. 80: Identifying Stop Light Control Relay (BRK NO. 1) And (BRK NO. 2)
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

NG: REPAIR OR REPLACE HARNESS OR CONNECTOR

OK: Go To Next Step

2. INSPECT STOP LIGHT CONTROL RELAY (BRK NO. 1, BRK NO. 2)

a. Remove the stop light control relays (BRK NO. 1 and BRK NO. 2) from the engine room relay

block.

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

Standard Resistance: for BRK NO. 1

TESTER CONNECTION SPECIFIED CONDITION TABLE

for BRK NO. 2

TESTER CONNECTION SPECIFIED CONDITION TABLE

Fig. 81: Identifying Stop Light Control Relays
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

Tester Connection

Switch Condition

Specified Condition

3-4

When battery voltage is not

applied to terminals 1 and 2

Below 1 ohms

3-5

When battery voltage is not

applied to terminals 1 and 2

10 kohms or higher

3-4

When battery voltage is applied

to terminals 1 and 2

10 kohms or higher

3-5

When battery voltage is applied

to terminals 1 and 2

Below 1 ohms

Tester Connection

Switch Condition

Specified Condition

3-4

When battery voltage is not

applied to terminals 1 and 2

Below 1 ohms

When battery voltage is applied

to terminals 1 and 2

10 kohms or higher

2009 Toyota Tundra

2009 BRAKES Brake Control - Tundra

NG: REPLACE STOP LIGHT CONTROL RELAY

OK: Go To Next Step

3. CHECK HARNESS AND CONNECTOR (ENGINE ROOM RELAY BLOCK - SKID CONTROL

ECU)

a. Disconnect the A17 ECU connector.

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

Standard Voltage

TESTER CONNECTION SPECIFIED CONDITION TABLE

Fig. 82: Identifying A17 Skid Control ECU Connector
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

NG: REPAIR OR REPLACE HARNESS OR CONNECTOR

OK: REPLACE VSC ACTUATOR ASSEMBLY (See DISASSEMBLY )

DTC C1336/39: ZERO POINT CALIBRATION OF ACCELERATION SENSOR UNDONE

DESCRIPTION

A new skid control ECU is supplied without zero point calibration for the deceleration sensor and master
cylinder pressure sensor. Until the zero points are calibrated, DTC C1336/39 remains stored. By entering test
mode, the zero point calibration is automatically performed, and DTC C1336/39 is erased automatically.

DTC DETECTION CONDITION TABLE

Tester Connection

Switch Condition

Specified Condition

A17-35 (BSW) - Body ground

Ignition switch ON

11 to 14 V

2009 Toyota Tundra

2009 BRAKES Brake Control - Tundra