9

Abnormal shifting

DESCRIPTION

• Shift incorrectly (incorrect shift pattern).

POSSIBLE CAUSE

• There is a malfunction in the signal circuit which controls shifting (Throttle position signal, turbine sensor, VSS), the control valve is stuck, or the clutch circuit is stuck.

• Clutch slippage, burnt (C1 clutch, C2 clutch, C3 clutch, B1 brake, B2 brake, B3 brake)

• Line pressure low

• Incorrect throttle position signal

• Incorrect accelerator pedal position signal

• Incorrect engine speed signal

• Incorrect engine coolant temperature signal

• Incorrect engine torque signal

• VSS malfunction

• Turbine sensor malfunction

• Sensor GND malfunction

• TFT sensor malfunction

• Line pressure control solenoid malfunction

• Body GND malfunction

• Control valve body malfunction

• TCM malfunction

NOTE:

• Before following the troubleshooting steps, make sure that the Automatic Transmission On-Board Diagnostic and Automatic Transmission Basic Inspection are conducted. (See BASIC INSPECTION [SJ6A-EL].)

STEP

INSPECTION

ACTION

1

• Inspect for continuity between the TCM terminal 1P, 1X and battery negative terminal.

• Is there continuity?

Yes

Go to the next step.

No

Repair or replace ground circuit.

2

• Access the following PCM PIDs using the M-MDS.

• RPM

• APP

• TP

• ECT

• ENG_TRQ

• Are PIDs value normal?

Yes

Go to the next step.

No

Inspect and repair suspected PID related part.

3

• Inspect the TFT sensor.

  (See TRANSMISSION FLUID TEMPERATURE (TFT) SENSOR INSPECTION [SJ6A-EL].)

• Is the TFT sensor normal?

Yes

Go to the next step.

No

Replace the TFT sensor.

4

• Inspect the line pressure control solenoid.

  (See SOLENOID VALVE INSPECTION [SJ6A-EL].)

• Is the line pressure control solenoid normal?

Yes

Inspect the TCM terminal for bend, damage, corrosion or poor contact.

No

Inspect the coupler component.

If normal, replace the control valve body.

(See CONTROL VALVE BODY REMOVAL [SJ6A-EL].)

(See CONTROL VALVE BODY INSTALLATION [SJ6A-EL].)

5

• Verify test results.

• If normal, return to the diagnostic index to service any additional symptoms.

• If malfunction remains, inspect the related Service Bulletins and/or On-line Repair Information and perform repair or diagnosis.

• If the vehicle is repaired, troubleshooting completed.

• If the vehicle is not repaired or additional diagnostic information is not available, replace the TCM.