Toyota Tundra Service Manual: Drive Start Control

DESCRIPTION

  • The drive start control is controlled by the ECM.

    If the ECM determines that the shift lever and accelerator pedal are operated abnormally, engine output is restricted and, when necessary, a warning is displayed on the combination meter assembly.

CAUTION / NOTICE / HINT

HINT:

Even if the accelerator pedal position is maintained, the engine output may increase when driving uphill and decrease when driving downhill. This is due to the drive start control controlling the engine output, and is not a malfunction.

PROCEDURE

1.

SYMPTOM CONFIRMATION

(a) Interview the customer to confirm the problem.

Result

Proceed to

Hunting

A

Hesitation/poor acceleration

B

B

GO TO STEP 8

A

2.

PAST ACTIVATION CONFIRMATION

(a) Check if the customer operated the vehicle in a way that would cause the drive start control to operate.

Drive Start Control Activation Conditions

Shift control
  • Activation conditions
  • Pattern A (When all of the following conditions are met, control starts.)
    • The accelerator pedal is open by approximately 1/5 or more.
    • The shift lever is moved from P to any forward position (D or S) or R.
  • Pattern B (When all of the following conditions are met, control starts.)
    • The accelerator pedal is open by approximately 1/5 or more.
    • The shift lever is moved from R to any forward position (D or S), any forward position (D or S) to R, or N to R.
  • Items Controlled
    • Engine output is restricted.
  • Deactivation Conditions
    • The accelerator pedal is released.
    • The shift lever is in P or N.
Reverse control
  • Activation conditions
  • The shift lever is in R.
  • The accelerator pedal is depressed excessively.
  • Items Controlled
    • Engine output is restricted.
  • Deactivation Conditions
    • The accelerator pedal is released.
    • The shift lever is moved to any position other than R.

HINT:

  • The engine output restricted level differs between pattern A, pattern B and Reverse control.
  • During reverse control or shift control, engine output is adjusted based on the road gradient and steering angle.

Result

Proceed to

Performed

A

Not performed

B

B

PROCEED TO PROBLEM SYMPTOM TABLE

A

3.

CHECK DTC OUTPUT

(a) Connect the Techstream to the DLC3.

(b) Turn the ignition switch to ON.

(c) Turn the Techstream on.

(d) Enter the following menus: System Select / Health Check.

(e) Check the DTCs.

Result

Proceed to

DTCs are not output

A

DTC is output

B

B

GO TO DTC CHART

A

4.

READ VALUE USING TECHSTREAM (FR, FL, RR, RL WHEEL SPEED)

(a) Connect the Techstream to the DLC3.

(b) Turn the ignition switch to ON.

(c) Turn the Techstream on.

(d) Start the engine.

(e) Enter the following menus: Chassis / ABS/VSC/TRC / Data List / FR Wheel Speed, FL Wheel Speed, RR Wheel Speed and RL Wheel Speed.

(f) Read the value displayed on the Techstream.

Standard:

Techstream Display

Condition

Specified Condition

FR Wheel Speed

FL Wheel Speed

RR Wheel Speed

RL Wheel Speed

Vehicle stopped, engine running

0 km/h (0 mph)

Vehicle being driven at constant speed between 16.1 to 64.4 km/h (10 to 40 mph)

No large fluctuations when driving at a constant speed

CAUTION:

When performing the confirmation driving pattern, obey all speed limits and traffic laws.

HINT:

Data can be captured relatively easily by using the snapshot function in the Data List. Confirm the data after performing the drive test.

NG

INSPECT FRONT OR REAR SPEED SENSOR

OK

5.

READ VALUE USING TECHSTREAM (SPD (SP2))

(a) Connect the Techstream to the DLC3.

(b) Turn the ignition switch to ON.

(c) Turn the Techstream on.

(d) Start the engine.

(e) Enter the following menus: Powertrain / Engine / Data List / SPD (SP2)

(f) Read the value displayed on the Techstream.

Standard:

Techstream Display

Condition

Specified Condition

SPD (SP2)

Vehicle stopped, engine running

0 rpm

Vehicle being driven at constant speed between 16.1 to 64.4 km/h (10 to 40 mph)

No large fluctuations when driving at a constant speed

CAUTION:

When performing the confirmation driving pattern, obey all speed limits and traffic laws.

HINT:

Data can be captured relatively easily by using the snapshot function in the Data List. Confirm the data after performing the drive test.

NG

INSPECT TRANSMISSION REVOLUTION SENSOR

OK

6.

READ VALUE USING TECHSTREAM (DECELERATION SENSOR)

(a) Connect the Techstream to the DLC3.

(b) Turn the ignition switch to ON.

(c) Turn the Techstream on.

(d) Start the engine.

(e) Enter the following menus: Chassis / ABS/VSC/TRC / Data List / Deceleration Sensor and Deceleration Sensor2.

(f) Read the value displayed on the Techstream.

Standard:

Techstream Display

Condition

Specified Condition

Deceleration Sensor

Deceleration Sensor2

During deceleration

Value changes with vehicle speed

During acceleration

Value changes with vehicle speed

CAUTION:

When performing the confirmation driving pattern, obey all speed limits and traffic laws.

HINT:

Data can be captured relatively easily by using the snapshot function in the Data List. Confirm the data after performing the drive test.

NG

INSPECT AIRBAG SENSOR ASSEMBLY

OK

7.

READ VALUE USING TECHSTREAM (STEERING ANGLE SENSOR)

(a) Connect the Techstream to the DLC3.

(b) Turn the ignition switch to ON.

(c) Turn the Techstream on.

(d) Start the engine.

(e) Enter the following menus: Chassis / ABS/VSC/TRC / Data List / Steering Angle Sensor.

(f) Read the value displayed on the Techstream.

Standard:

Techstream Display

Condition

Specified Condition

Steering Angle Sensor

Steering wheel turned left

Value increases with steering wheel operation

Steering wheel turned right

Value decreases with steering wheel operation

CAUTION:

When performing the confirmation driving pattern, obey all speed limits and traffic laws.

HINT:

Data can be captured relatively easily by using the snapshot function in the Data List. Confirm the data after performing the drive test.

OK

SYSTEM NORMAL (GO TO PROBLEM SYMPTOM TABLE)

NG

INSPECT STEERING ANGLE SENSOR

8.

PAST ACTIVATION CONFIRMATION

(a) Check if the customer operated the vehicle in a way that would cause the drive start control to operate.

Drive Start Control Activation Conditions

Shift control
  • Activation conditions
  • Pattern A (When all of the following conditions are met, control starts.)
    • The accelerator pedal is open by approximately 1/5 or more.
    • The shift lever is moved from P to any forward position (D or S) or R.
  • Pattern B (When all of the following conditions are met, control starts.)
    • The accelerator pedal is open by approximately 1/5 or more.
    • The shift lever is moved from R to any forward position (D or S), any forward position (D or S) to R, or N to R.
  • Items Controlled
    • Engine output is restricted.
  • Deactivation Conditions
    • The accelerator pedal is released.
    • The shift lever is in P or N.
Reverse control
  • Activation conditions
  • The shift lever is in R.
  • The accelerator pedal is depressed excessively.
  • Items Controlled
    • Engine output is restricted.
  • Deactivation Conditions
    • The accelerator pedal is released.
    • The shift lever is moved to any position other than R.

HINT:

  • The engine output restricted level differs between pattern A, pattern B and Reverse control.
  • During reverse control or shift control, engine output is adjusted based on the road gradient and steering angle.

Result

Proceed to

Performed

A

Not performed

B

A

SYSTEM NORMAL

B

9.

CHECK DTC OUTPUT

(a) Connect the Techstream to the DLC3.

(b) Turn the ignition switch to ON.

(c) Turn the Techstream on.

(d) Enter the following menus: System Select / Health Check.

(e) Check the DTCs.

Result

Proceed to

DTCs are not output

A

DTC is output

B

B

GO TO DTC CHART

A

10.

INSPECT PARK/NEUTRAL POSITION SWITCH ASSEMBLY

(a) Inspect the park/neutral position switch assembly.

  • for 2WD

    Click here

  • for 4WD

    Click here

Result

Proceed to

Normal

A

Abnormal

B

B

REPLACE PARK/NEUTRAL POSITION SWITCH ASSEMBLY

A

11.

READ VALUE USING TECHSTREAM (ACCELERATOR PEDAL POSITION SENSOR)

(a) Connect the Techstream to the DLC3.

(b) Turn the ignition switch to ON.

(c) Turn the Techstream on.

(d) Enter the following menus: Powertrain / Engine / Data List / Accelerator Position Sensor No.1 Voltage % and Accelerator Position Sensor No.2 Voltage %.

(e) Read the value displayed on the Techstream.

OK:

Techstream Display

Condition

Specified Condition

Accelerator Position Sensor No.1 Voltage %

Accelerator Pedal Released → Depressed

Values smoothly change following accelerator pedal operation

Accelerator Position Sensor No.2 Voltage %

HINT:

For numerical values of Accelerator Position Sensor No.1 Voltage % and Accelerator Position Sensor No.2 Voltage %, refer to the Data List.

Click here

OK

SYSTEM NORMAL (GO TO PROBLEM SYMPTOM TABLE)

NG

REPLACE ACCELERATOR PEDAL SENSOR ASSEMBLY

    Diagnostic Trouble Code Chart

    Dtc Check / Clear

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