Last Modified: 11-29-2007 1.6 C
Service Category: Brake Section: Brake Control/Dynamic Control System
Model Year: 2008 Model: Sequoia Doc ID: RM000001MXO005X
Title: BRAKE CONTROL / DYNAMIC CONTROL SYSTEMS: VEHICLE STABILITY CONTROL SYSTEM: DESCRIPTION (2008 Sequoia)

DTC

C1247/47

Stroke Sensor Malfunction

DESCRIPTION

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

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 0.1 seconds.
  2. When the output does not return to 2.5 V even when 0.5 seconds or more elapse, in spite of no change in brake operation.
  • Brake booster
  • Pedal stroke sensor
  • Pedal stroke sensor circuit
  • VSC actuator (skid control ECU)

WIRING DIAGRAM

INSPECTION PROCEDURE

NOTICE:

When replacing the VSC actuator assembly, perform zero point calibration BRAKE CONTROL / DYNAMIC CONTROL SYSTEMS: VEHICLE STABILITY CONTROL SYSTEM: CALIBRATION (2008 Sequoia) .

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 3000 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

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.

-

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 pedal stroke sensor displayed on the Techstream changes by alternately depressing and releasing the brake pedal.

OK:

The value changes as shown in the illustration. (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.

NEXT

2.

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

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

(b) Disconnect the A19 ECU connector.

(c) Disconnect the A21 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

Condition

Specified Condition

A19-18 (PIM) - A21-5 (PIM)

Always

Below 1 Ω

A19-18 (PIM) - Body ground

Always

10 kΩ or higher

A19-21 (E3) - A21-3 (E3)

Always

Below 1 Ω

A19-21 (E3) - Body ground

Always

10 kΩ or higher

A19-22 (VCP) - A21-1 (VCP)

Always

Below 1 Ω

A19-22 (VCP) - Body ground

Always

10 kΩ or higher
OK

3.

INSPECT BRAKE BOOSTER ASSEMBLY (PEDAL STROKE SENSOR)

(a) Disconnect the A21 sensor connector.

(b) Turn the ignition switch to ON.

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

Standard Voltage:

Tester Connection

Switch Condition

Specified Condition

A21-1 (VCP) - Body ground

Ignition switch ON

5.0 V
OK