Toyota Tundra. Manual — part 935

Fig. 59: Identifying A17 ECU Connector Terminals
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

NG: REPAIR OR REPLACE HARNESS OR CONNECTOR

OK: Go To Next Step

4. RECONFIRM DTC

a. Clear the DTCs (See DTC CHECK/CLEAR ).

b. Start the engine.

c. Check if the same DTCs are output (See DTC CHECK/CLEAR ).

Result

RESULT TABLE

B: USE SIMULATION METHOD TO CHECK (See HOW TO PROCEED WITH
TROUBLESHOOTING )

A: REPLACE VSC ACTUATOR ASSEMBLY (See REMOVAL )

DTC C1247/47: STROKE SENSOR MALFUNCTION

DESCRIPTION

Detects a problem with booster vacuum pressure and enters assist control.

DTC DETECTION CONDITION TABLE

Result

Proceed to

DTC is output

A

DTC is not output

B

2009 Toyota Tundra

2009 BRAKES Brake Control - Tundra

WIRING DIAGRAM

Fig. 60: Identifying Stroke Sensor Malfunction - Wiring Diagram
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

INSPECTION PROCEDURE

1. READ VALUE USING TECHSTREAM (STROKE SENSOR)

a. Connect the Techstream to the DLC3.

b. Turn the ignition switch to ON.

c. Run the engine until the engine reaches 3,000 rpm, and return it back to idle.

HINT:

Rev up the engine to ensure a sufficient vacuum.

d. Select the Data List mode on the Techstream.

ABS/VSC/TRAC

DTC Code

DTC Detection Condition

Trouble Area

C1247/47

When either condition below is
met:

1. When the output becomes

4.7 V or more or 0.2 V or
less per 100 msec.

2. When the output does not

return to 2.5 V even when
0.5 sec. or more elapse, in
spite of no change in brake
operation.



Brake booster



Pedal stroke sensor



Pedal stroke sensor circuit



Skid control ECU

NOTE:

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

2009 Toyota Tundra

2009 BRAKES Brake Control - Tundra

DIAGNOSTIC NOTE TABLE

HINT:



The result appears on the Techstream after some delay because a time lag occurs when using
the Techstream.



If a signal from the pedal stroke sensor is sent between sampling, the result does not appear
on the Techstream. So be sure to perform the measurement 2 or 3 times.

e. Check that the brake pedal acceleration value of the delta S sensor displayed on the Techstream

changes by alternately depressing and releasing the brake pedal.

OK: The value changes as shown below.

(The value will return to approximately 1.9 V after the brake pedal is released.)

HINT:



The maximum voltage depends on pedal stroke speed but should not exceed 4.7 V or fall
below 0.2 V.



Even if the result is as described above, a malfunction may still exist because there is a high
possibility that the malfunction simulation will fail. Therefore, proceed to the troubleshooting
procedures below.

Fig. 61: Identifying Voltage Graph
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

2. CHECK HARNESS AND CONNECTOR (PEDAL STROKE SENSOR - SKID CONTROL ECU)

Tester Display

Measurement

Item/Range

Normal Condition

Diagnostic Note

Stroke Sensor

Pedal stroke sensor /
min.: 0.2 V, max.: 4.7 V

Approximately 1.9 V
without the brake pedal
depressed.

-

2009 Toyota Tundra

2009 BRAKES Brake Control - Tundra

a. Confirm that the skid control ECU connector and pedal stroke sensor connector are properly

connected.

b. Disconnect the A17 ECU connector.

c. Disconnect the A19 sensor connector.

d. Inspect both the connector case and the terminal for deformation and corrosion.

OK: No deformation or corrosion.

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

Standard Resistance

TESTER CONNECTION SPECIFIED CONDITION TABLE

Fig. 62: Identifying A17 Skid Control ECU Connector & A19 Pedal Stroke Sensor Connector
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

Tester Connection

Condition

Specified Condition

A17-18 (PIM) - A19-5 (PIM)

Always

Below 1 ohms

A17-18 (PIM) - Body ground

Always

10 kohms or higher

A17-21 (E3) - A19-3 (E3)

Always

Below 1 ohms

A17-21 (E3) - Body ground

Always

10 kohms or higher

A17-22 (VCP) - A19-1 (VCP)

Always

Below 1 ohms

A17-22 (VCP) - Body ground

Always

10 kohms or higher

2009 Toyota Tundra

2009 BRAKES Brake Control - Tundra