Inspection Procedure

HINT:

Read freeze frame data using hand-held tester or OBD II scan tool. Because freeze frame records the engine conditions when a malfunction is detected. When troubleshooting, it is useful for determining whether the vehicle was running or stopped, the engine was warmed up or not, etc. at the time of the malfunction.

1. Check if there is any sequential transmission fluid leakage. 

   NG: Repair or replace (see  GEAR SHIFT ACTUATOR  or  HYDRAULIC POWER UNIT  ). 

   OK: Go to next step. 

2. Connect hand-held tester, check accumulator pressure. 

   PREPARATION: 

   1. Turn the ignition switch ON.
   2. Start the engine and warm it up.
   3. Connect the hand-held tester to the DLC3.
   4. Fix the position at 1st gear.

   CHECK: 

   Read the accumulator pressure value using the hand-held tester.

   OK: Pressure drops by approximately 3.5 bar per minute 

   NG: Replace HPU assembly. 

   OK: Go to next step. 

3. Check for open and short in harness and connector between clutch stroke sensor, clutch solenoid and transmission control ECU (see  HOW TO USE THE DIAGNOSTIC CHART AND INSPECTION PROCEDURE  ). 

   NG: Repair or replace harness and connector. 

   OK: Go to next step. 

4. Connect hand-held tester, read value of clutch stroke sensor. 

   PREPARATION: 

   1. Turn the ignition switch ON.
   2. Stop the engine.
   3. Release the brake pedal.
   4. Connect the hand-held tester to the DLC3.

   CHECK: 

   Read the clutch stroke sensor value by using the hand-held tester.

   OK: 

   CLUTCH STROKE SENSOR VALUE SPECIFICATION TABLE
   
   

   Shift Lever Position	Clutch Stroke Sensor Value
   N	Approx. 30 mm (1.181 in.)
   S	Approx. 20 mm (0.787 in.)

   OK: Go to step   6 . 

   NG: Go to next step. 

5. Check clutch solenoid. 

   PREPARATION: 

   Disconnect the HPU connector.

   CHECK: 

   1. Apply battery positive voltage between terminals 3 and 5 of the HPU assembly connector and use a sound scope to check that there is normal operating sound of the clutch solenoid while it is operating.
   Fig 1: Applying Battery Positive Voltage Between Terminals 3 And 5 Of HPU Assembly Connector
   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   2. Measure the resistance of the terminals 3 and 5 of the HPU assembly connector.
      Fig 2: Measuring Resistance Of Terminals 3 And 5 Of HPU Assembly Connector

      Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      OK: 

   1. Operation: There is operating sound of the clutch solenoid. 
   2. Resistance: 5.32 - 5.88 Ω at 20°C (68°F) 

   NG: Replace HPU assembly. 

   OK: Go to next step. 

6. Inspect clutch stroke sensor. 

   PREPARATION: 

   Remove the clutch stroke sensor.

   CHECK: 

   Check the voltage of the clutch stroke sensor.

   1. Connect 3 dry cell batteries (1.5 V) in series.
   2. Connect the battery positive (+) wire to terminal A and the battery negative (-) wire to terminal C.
   3. Check the voltage between terminals C and B when moving the link.
      Fig 3: Checking Voltage Of Clutch Stroke Sensor

      Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   OK: Voltage (Power source voltage at 4.5V): 

   SENSOR ANGLE SPECIFICATION TABLE
   
   

   Sensor angle (degree)	Terminal (C - B) output voltage (V)
   44.8	4.127 - 4.306
   135.5	0.185 - 0.364

   HINT:

   Formula when the power source voltage has changed. (4V le power source le 6V) 

   SENSOR ANGLE SPECIFICATION TABLE
   
   

   Sensor angle (degree)	Output voltage (V)
   44.8	Power source x (0.937 +/- 0.02)
   135.5	Power source x (0.061 +/- 0.02)

   NG: Replace clutch stroke sensor. 

   OK: Go to next step. 

7. Replace HPU and GSA. 

   After replacing the HPU and GSA, check that the problem disappears.

   NG: Replace transmission control ECU. 

   OK: END.