Automatic Transmission - Diagnostics: Pre-Check

1. Description
   • When troubleshooting vehicles with OBD II, the only difference from the usual troubleshooting procedure is that you connect an OBD II scan tool complying with SAE J1987 or hand-held tester to the vehicle, and read off various data output from the vehicle's ECM.
   • OBD II regulations require that the vehicle's on board computer lights up the Malfunction Indicator Lamp (MIL) on the instrument panel when the computer detects a malfunction in the computer itself or in drive system components which affect vehicle emissions. In addition to the MIL lighting up when a malfunction is detected, the applicable DTCs prescribed by SAE J2012 are recorded in the ECM memory (See PROBLEM SYMPTOMS TABLE ).

     If the malfunction does not occur in 3 consecutive trips, the MIL goes off but the DTCs remain recorded in the ECM memory.

     Fig 1: Identifying Malfunction Indicator Lamp

     Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   • To check the DTCs, connect an OBD II scan tool or hand-held tester to DLC3 on the vehicle. The OBD II scan tool or hand-held tester also enables you to erase the DTCs and check freeze frame data and various forms of engine data (For operating instructions, see the instruction book).
     Fig 2: Connecting Hand-Held Tester To DLC3

     Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   • DTCs include SAE controlled codes and Manufacturer controlled codes.

     SAE controlled codes must be set as the codes prescribed by the SAE, while Manufacturer controlled codes can be set freely by the manufacturer within the prescribed limits (See DTC chart on DIAGNOSTIC TROUBLE CODE CHART ).

   • The diagnosis system operates in normal mode during normal vehicle use, and also has a check mode for technicians to simulate malfunction symptoms and perform troubleshooting. Most DTCs use 2-trip detection logic (*) to prevent erroneous detection. By switching the ECM to check mode when troubleshooting, the technician can cause the MIL to light up for a malfunction that is only detected once or momentarily.

     (Hand-held tester) (See PRE-CHECK )

   • *2-trip detection logic:

     When a logic malfunction is first detected, the malfunction is temporarily stored in the ECM memory. If the same malfunction is detected again during the 2nd test drive, this 2nd detection causes the MIL to light up. The 2-trip repeats the same mode 2nd time (However, the IG switch must be turned OFF between the 1st trip and 2nd trip.).

2. Inspect the DLC3.

   The vehicle's ECM uses the ISO 9141-2 communication protocol. The terminal arrangement of DLC3 complies with SAE J1962 and matches the ISO 9141-2 format.

Fig 3: Inspecting DLC3

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HINT:

If your display shows "UNABLE TO CONNECT TO VEHICLE" when you have connected the cable of OBD II scan tool or hand-held tester to DLC3, turned the ignition switch ON and operated the scan tool, there is a problem on the vehicle side or tool side.

• If communication is normal when the tool is connected to another vehicle, inspect DLC3 on the original vehicle.
• If communication is still not possible when the tool is connected to another vehicle, the problem is probably in the tool itself, so consult the Service Department listed in the tool's instruction manual.

HINT:

DTCs can be displayed on the OBD II scan tools. The hand held tester displays the current DTCs and pending DTCs. Some DTCs are set when the same malfunction is detected in consecutive driving cycle. The pending DTCs are set when the malfunction is detected once.

1. Check the MIL.
   1. The MIL comes on when the ignition switch is turned ON and the engine is not running.

      HINT:

      If the MIL does not light up, troubleshoot the combination meter (See PROBLEM SYMPTOMS TABLE ).

   2. When the engine is started, the MIL should go off. If the lamp remains on, the diagnosis system has detected a malfunction or abnormality in the system.
   Fig 4: Identifying Malfunction Indicator Lamp

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
2. Check the DTC.
   NOTE: Hand-held tester only: When the diagnostic system is switched from normal mode to check mode, it erases all DTCs and freeze frame data recorded in normal mode. So before switching modes, always check the DTCs and freeze frame data, and note them down. 
   1. Prepare an OBD II scan tool (complying with SAE J1978) or hand-held tester.
   2. Connect the OBD II scan tool or hand-held tester to DLC3 at the lower of the instrument panel.
      Fig 5: Connecting Hand-Held Tester To DLC3

      Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   3. Turn the ignition switch ON and turn the OBD II scan tool or hand-held tester switch ON.
   4. Use the OBD II scan tool or hand-held tester to check the DTCs and freeze frame data and note them down (For operating instructions, see the OBD II scan tool's instruction book).
   5. See DIAGNOSTIC TROUBLE CODE CHART  to confirm the details of the DTCs.
   NOTE: When simulating symptoms with an OBD II scan tool (excluding hand-held tester) to check the DTCs, use normal mode. For codes on the DTCs chart subject to "2-trip detection logic", turn the ignition switch off after the symptoms have been simulated the 1st time. Then repeat the simulation process again. When the problem has been simulated twice, the MIL comes on the instrument panel and the DTCs are recorded in the ECM. 
3. When using the OBD II scan tool or hand-held tester: Clearing the DTCs.
   1. Connect the OBD II scan tool or hand-held tester to the DLC3.
   2. Turn the ignition switch to the ON position and push the OBD II scan tool or the hand-held tester main switch on.
   3. When you use hand-held tester:

      Select the item "DIAGNOSIS / ENHANCED OBD II / DTC INFO / CLEAR CODES [YES] button".

   HINT:

   When operating the OBD II scan tool (complying with SAE J1978) or hand-held tester to erase the codes, the DTCs and freeze frame data will be erased. (See the OBD II scan tool's instruction book for operating instructions.)

4. When not using the OBD II scan tool or hand-held tester: Clearing the DTCs.

   Disconnect the battery terminal or remove the EFI and ETCS fuses from the engine room J/B for 60 seconds or more.

HINT:

Hand-held tester only: Compared to the normal mode, the check mode has high sensing ability to detect malfunctions. Furthermore, the same diagnostic items which are detected in Normal mode can also be detected in Check mode.

1. Check the DTC.
   1. Check the initial conditions.
      • Battery voltage 11 V or more
      • Throttle valve fully closed
      • Shift lever in P position
      • Air conditioning switched off
   2. Turn the ignition switch off.
   3. Prepare a hand-held tester.
   4. Connect the hand-held tester to DLC3 at the lower side of the instrument panel.
      Fig 6: Connecting Hand-Held Tester To DLC3

      Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   5. Turn the ignition switch ON and switch the hand held tester ON.
   6. Switch the hand-held tester from Normal mode to Check mode (Check that the MIL flashes).
      Fig 7: Checking MIL Flashes

      Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   7. Start the engine (MIL goes out after the engine starts).
   8. Simulate the conditions of the malfunction described by the customer.
      NOTE: Leave the ignition switch ON until you have checked the DTCs, etc. 
   9. After simulating the malfunction conditions, use the hand-held tester diagnosis selector to check the DTCs and freeze frame data, etc.

      HINT:

      Be sure not to turn the ignition switch off as turning it off switches the diagnosis system from Check mode to Normal mode, which erases all DTCs, etc.

   10. After checking the DTC, inspect the applicable circuit.
2. When using the OBD II scan tool or hand-held tester: Clearing the DTCs.
   1. Connect the OBD II scan tool or hand-held tester to the DLC3.
   2. Turn the ignition switch to the ON position and push the OBD II scan tool or the hand-held tester main switch on.
   3. When you use hand-held tester:

      Select the item "DIAGNOSIS / ENHANCED OBD II / DTC INFO / CLEAR CODES [YES] button".

   HINT:

   When operating the OBD II scan tool (complying with SAE J1978) or hand-held tester to erase the codes, the DTCs and freeze frame data will be erased. (See the OBD II scan tool's instruction book for operating instructions.)

3. When not using the OBD II scan tool or hand-held tester: Clearing the DTCs.

   Disconnect the battery terminal or remove the EFI and ETCS fuses from the engine room J/B for 60 seconds or more.

HINT:

According to the DATA LIST displayed by the OBD II scan tool or hand-held tester, you can read the value of the switch, sensor, actuator and so on without parts removal. Reading the DATA LIST as the first step of troubleshooting is one of the methods to shorten the labor time.

1. Warm up the engine.
2. Turn the ignition switch off.
3. Connect the OBD II scan tool or hand-held tester to the DLC3.
4. Turn the ignition switch to the ON position.
5. Push the "ON" button of the OBD II scan tool or the hand-held tester.
6. Select the item "DIAGNOSIS / ENHANCED OBD II / DATA LIST".
7. According to the display on tester, read the "DATA LIST".

Fig 8: Data List Reference Chart

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HINT:

Performing the ACTIVE TEST using the hand-held tester allows the relay, VSV, actuator and so on to operate without parts removal. Performing the ACTIVE TEST as the first step of troubleshooting is one of the methods to shorten the labor time.

It is possible to display the DATA LIST during the ACTIVE TEST.

1. Warm up the engine.
2. Turn the ignition switch off.
3. Connect the hand-held tester to the DLC3.
4. Turn the ignition switch to the ON position.
5. Push the "ON" button of the hand-held tester.
6. Select the item "DIAGNOSIS / ENHANCED OBD II / ACTIVE TEST".
7. According to the display on tester, perform the "ACTIVE TEST".

Fig 9: Active Test Chart

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

This reference list indicates the part names used in this manual along with their definitions.

HINT:

This table indicates ECM monitoring status for the items in the upper columns if the DTCs in each line on the left are being set.

As for the "X" mark, when the DTC on the left is stored, detection of the DTC in the upper column is not performed.

Fig 10: Monitor Disablement Chart (1 Of 6)

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Fig 11: Monitor Disablement Chart (2 Of 6)

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Fig 12: Monitor Disablement Chart (3 Of 6)

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Fig 13: Monitor Disablement Chart (4 Of 6)

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Fig 14: Monitor Disablement Chart (5 Of 6)

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Fig 15: Monitor Disablement Chart (6 Of 6)

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Taking into consideration the results of the customer problem analysis, try to reproduce the symptoms of the trouble. If the problem is that the transaxle does not up-shift, down-shift, or the shift point is too high or too low, conduct the following road test to confirm the automatic shift schedule and simulate the problem symptoms.

1. D position test (NORM and PWR pattern):

   Shift into the D position and fully depress the accelerator pedal and check the following points.

   1. Check up-shift operation.

      Check that 1 Ω 2, 2 -> 3, 3 -> 4 and 4 -> 5th up-shifts take place, and that the shift points conform to the automatic shift schedule (See SERVICE DATA ).

      HINT:

      • 5th Gear Up-shift Prohibition Control (1. Coolant temp, is 60 °C(140 °F) or less. 2. If there is a 10 km/h (6 mph) difference between the set cruise control speed and vehicle speed.)
      • 5th Gear Lock-up Prohibition Control (1. Brake pedal is depressed. 2. Coolant temp, is 60°C (140°F) or less.)
   2. Check for shift shock and slip.

      Check for shock and slip at the 1 Ω 2, 2 -> 3, 3 -> 4 and 4 -> 5th up-shifts.

   3. Check for abnormal noises and vibration.

      Drive in the D position lock-up or 5th gear and check for abnormal noises and vibration.

      HINT:

      The check for the cause of abnormal noises and vibration must be done very thoroughly as it could also be due to loss of balance in the differential, torque converter clutch, etc.

   4. Check kick-down operation.

      While driving in the D position, 2nd, 3rd, 4th and 5th gears, check that the possible kick-down vehicle speed limits for 2 - 1, 3 -> 2, 4 -> 3 and 5 -> 4th kick-downs conform to those indicated on the automatic shift schedule (See SERVICE DATA ).

   5. Check abnormal shock and slip at kick-down.
   6. Check the lock-up mechanism.
      • Drive in D position 5th gear, at a steady speed (lock-up ON) of about 70 km/h (43 mph).
      • Lightly depress the accelerator pedal and check that the engine speed does not change abruptly.

   If there is a big jump in engine speed, there is no lock-up.

2. 4 position test:

   With the shift lever in "M", press the shift down switch once and check that the gear position indicator show "4". Fully depress the accelerator pedal and check the following points.

   1. Check up-shift operation.

      Check that the 1 Ω 4 up-shift takes place and that the shift point conforms to the automatic shift schedule (See SERVICE DATA ).

      HINT:

      There is no 5th up-shift in the 4 position.

   2. Check engine braking.

      While driving in the 4 position and 4th gear, release the accelerator pedal and check the engine braking effect.

   3. Check for abnormal noises during acceleration and deceleration, and for shock at up-shift and down-shift.
3. 3 position test:

   Shift into the 3 position and fully depress the accelerator pedal and check the following points.

   1. Check up-shift operation.

      Check that the 1 Ω 3 up-shift takes place and that the shift point conforms to the automatic shift schedule (See SERVICE DATA ).

   2. Check engine braking.

      While driving in the 3 position and 3rd gear, release the accelerator pedal and check the engine braking effect.

   3. Check for abnormal noises during acceleration and deceleration, and for shock at up-shift and down-shift.
4. 2 position test:

   Shift into the 2 position and fully depress the accelerator pedal and check the following points.

   1. Check up-shift operation.

      Check that the 1 Ω 2 up-shift takes place and that the shift point conforms to the automatic shift schedule (See SERVICE DATA ).

   2. Check engine braking.

      While driving in the 2 position and 2nd gear, release the accelerator pedal and check the engine braking effect.

   3. Check for abnormal noises during acceleration and deceleration, and for shock at up-shift and down-shift.
5. L position test:

   Shift into the L position and fully depress the accelerator pedal and check the following points.

   1. Check no up-shift.

      While driving in the L position, check that there is no up-shift to 2nd gear.

   2. Check engine braking.

      While driving in the L position, release the accelerator pedal and check the engine braking effect.

   3. Check for abnormal noises during acceleration and deceleration.
6. R position test

   Shift into the R position, lightly depress the accelerator pedal, and check that the vehicle moves backward without any abnormal noise or vibration.

   CAUTION: Before conducting this test ensure that the test area is free from people and obstruction. 
7. P position test:

   Stop the vehicle on a grade (more than 5°) and after shifting into the P position, release the parking brake. Then check that the parking lock pawl holds the vehicle in place.

1. Check the idling speed.
   1. Idling speed (In N position and air conditioning OFF): 700 +/- 50 rpm 

   HINT:

   If the idling speed is outside the standard range, the fluid level check may be inaccurate.

2. Check the fluid level.

   HINT:

   • Drive the vehicle so that the engine and transmission are at normal operating temperature.
     1. Fluid temp.: 70 to 80°C (158 to 176°F) 
   • Only use the COOL range on the dipstick as a rough reference when the fluid is changed or the engine does not run.
   1. Park the vehicle on a level surface and set the parking brake.
   2. With the engine idling and the brake pedal depressed, shift the shift lever into all positions from P to L position and return to P position.
   3. Pull out the dipstick and wipe it clean.
   4. Push it back fully into the pipe.
   5. Pull it out and check that the fluid level is in the HOT range.

   If the level is not within the range, add new fluid.

   1. Fluid type: ATF T-IV 
   NOTE: Do not overfill. 
   Fig 16: Checking Fluid Level

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
3. Check the fluid condition.

   If the fluid smells burnt or is black, change it.

4. Replace the ATF.
   1. Remove the drain plug and drain the fluid.
   2. Reinstall the drain plug securely.
      1. Torque: 20 N.m (205 kgf.cm, 15 ft.lbf) 
   3. With the engine OFF add new fluid through the oil filler pipe.
      1. Fluid type: ATF T-IV 
      2. Capacity: 2.0 liters (2.1 US qts, 1.8 Imp. qts) 
      Fig 17: Adding Fluid Through Oil Filler Pipe

      Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   4. Start the engine and shift the shift lever into all positions from P to L position and then shift into P position.
   5. With the engine idling, check the fluid level. Add fluid up to the COOL level on the dipstick.
   6. Check the fluid level is at the normal operating temperature, 70 to 80 °C (158 to 176 °F), and add as necessary.
      Fig 18: Checking Fluid Level

      Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   NOTE: Do not overfill. 
5. Check the fluid leaks.

   Check for leaks in the transmission.

   If there are leaks, it is necessary to repair or replace O-rings, FIPGs, oil seals, plugs or other parts.

6. Inspect and adjust the shift lever position.

   When shifting the shift lever from the N position to other positions, check that the lever can be shifted smoothly and accurately to each position and that the position indicator is aligned with the correct position.

   If the indicator is not aligned with the correct position, carry out the following adjustment procedures.

   Fig 19: Inspecting & Adjusting Park/Neutral Position Switch

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   1. Loosen the nut on the shift lever.
   2. Push the control shaft fully in toward the rear of the vehicle.
   3. Return the control shaft lever 2 notches to N position.
   4. Set the shift lever to N position.
   5. While holding the shift lever lightly toward the R position side, tighten the shift lever nut.
      1. Torque: 13 N.m (130 kgf.cm, 10 ft.lbf) 
   6. Start the engine and make sure that the vehicle moves forward when shifting the lever from the N to D position and reverses when shifting it to the R position.
7. Inspect and adjust the park/neutral position switch.
   • Check that the engine can be started with the shift lever only in the N or P position, but not in other positions.
     Fig 20: Inspecting And Adjusting Park/Neutral Position Switch

     Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   If it is not as stated above, carry out the following adjustment procedures.

   • Loosen the park/neutral position switch bolt and set the shift lever to the N position.
   • Align the groove and neutral basic line.
   • Hold the switch in position and tighten the bolt.

1. Torque: 13 N.m (130 kgf.cm, 10 ft.lbf) 

• For continuity inspection of the park/neutral position switch, see DTC P0705 Transmission Range Sensor Circuit Malfunction (PRNDL Input) .

1. Measure the stall speed.

   The object of this test is to check the overall performance of the transmission and engine by measuring the stall speeds in the D position.

   NOTE:

   • Do the test at normal operating fluid temperature 50 to 80°C (122 to 176°F). 
   • Do not continuously run this test for longer than 5 seconds. 
   • To ensure safety, conduct this test in a wide, clear level area which provides good traction. 
   • The stall test should always be carried out in pairs. One technician should observe the conditions of wheels or wheel stoppers outside the vehicle while the other is doing the test. 
   • Chock the 4 wheels.
   • Connect an OBD II scan tool or hand-held tester to DLC3.
   • Fully apply the parking brake.
   • Keep your left foot depressing firmly on the brake pedal.
   • Start the engine.
   • Shift into the D position. Press all the way down on the accelerator pedal with your right foot. Quickly read the stall speed at this time.
   1. Stall speed: 
   2. 2,700 +/- 150 rpm 

   Evaluation: 

   Fig 21: Evaluatio Of Stall Speed Chart

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
2. Measure the time lag.

   When the shift lever is shifted while the engine is idling, there will be a certain time lapse or lag before the shock can be felt. This is used for checking the condition of the O/D direct clutch, forward clutch, and 1st & reverse brake.

   NOTE:

   • Do the test at normal operating fluid temperature 50 to 80 °C (122 to 176 °F). 
   • Be sure to allow 1 minute interval between tests. 
   • Take 3 measurements and take the average value. 
   • Fully apply the parking brake.
   • Start the engine and check idle speed.
   1. Idle speed (In N position and air conditioner OFF): 
   2. 700 +/- 50 rpm 
   • Shift the shift lever from N to D position. Using a stop watch, measure the time from when the lever is shifted until the shock is felt.
   1. Time lag: N +/- D Less than 1.2 seconds 
   • In the same manner, measure the time lag for N -> R.
   1. Time lag: N -> R Less than 1.5 seconds 

   Evaluation (If N -> D or N -> R time lag is longer than the specified): 

   Fig 22: Evaluation (If N->D Or N->R Time Lag Is Longer

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Measure the line pressure.

1. Warm up the ATF.
2. Remove the test plug on the front left side of the transmission case and connect SST (See AUTOMATIC TRANSMISSION UNIT for the location to connect SST).
   1. SST 09992-00095 (09992-00231, 09992-00271)
3. Fully apply the parking brake and chock the 4 wheels.
4. Start the engine and check idling speed.
5. Keep your left foot pressing firmly on the brake pedal and shift into D position.
6. Measure the line pressure when the engine is idling.
7. Depress the accelerator pedal all the way down. Quickly read the highest line pressure when engine speed reaches stall speed.
8. In the same manner, do the test in R position.

If the measured pressures are not up to the specified values, recheck the throttle cable adjustment and re-test.

Evaluation 

Fig 23: Transmission Evaluation Chart

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The purpose of this manual shifting test is to determine whether a problem is caused by either mechanical or electrical factors. Disconnecting the solenoid wire disables electrically-controlled automatic gear shifting. In this case, operating the shift level is the only way to shift the transmission gear. If the gear is not changed by shift lever operation, it is assumed that there is a mechanical problem.

Fig 24: Disconnecting Solenoid Wire

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1. Turn the ignition switch OFF.
2. Disconnect the solenoid wire connector.
3. Warm up the engine.
4. Drive the vehicle.
5. Check the transmission operation when the shift lever is moved into L, 2, 3, M and D ranges.

   Standard: 

   Shift Lever	Operation
   L to 2	No shift (Not change)
   2 to 3	Up shift
   3 to M	Up shift
   M to D	No shift (Not change)
   D to M	No shift (Not change)
   M to 3	Down shift
   3 to 2	Down shift
   2 to L	No shift (Not change)

6. Turn the ignition switch OFF.
7. Connect the solenoid wire connector.
8. Clear DTCs.

   HINT:

   When the solenoid wire is disconnected, the transmission gear will be set as listed below.

   Shift Lever	Gear
   P	Parking
   R	Reverse
   N	Neutral
   D and M	5th
   3	4th
   2 and L	3rd

HINT:

The ECM memorizes the condition that the ECT controls the automatic transmission assy and engine assy according to those characteristics. Therefore, when the automatic transmission assy, engine assy, or ECM has been replaced, it is necessary to reset the memory so that the ECM can memorize the new information. Reset procedure is as follows.

1. Turn the ignition switch off.
2. Connect the hand-held tester to the DLC3.
3. Turn the ignition switch to the ON position and push the hand-held tester main switch on.
4. Select the item "DIAGNOSIS / ENHANCED OBD II".
5. Perform the reset memory procedure from the ENGINE menu.

Fig 25: Tester Menu Flow Chart

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