Inspection Procedure

HINT:

Read freeze frame data using the intelligent tester. The ECM records vehicle and driving condition information as freeze frame data the moment a DTC is stored. When troubleshooting, freeze frame data can be helpful in determining whether the vehicle was running or stopped, whether the engine was warmed up or not, whether the air-fuel ratio was lean or rich, as well as other data recorded at the time of a malfunction (See FREEZE FRAME DATA ).

1. CHECK SPEEDOMETER 
   1. Drive the vehicle and check whether the operation of the speedometer in the combination meter is normal.

      HINT:

      • The vehicle speed sensor is operating normally if the speedometer reading is normal.
      • If the speedometer does not operate, check it by following the procedure described in speedometer circuit.

   NG: GO TO SPEEDOMETER CIRCUIT 

   OK: Go to Next Step 

2. READ VALUE OF INTELLIGENT TESTER (VEHICLE SPEED) 
   1. Connect the intelligent tester to the DLC3.
   2. Turn the engine switch on (IG).
   3. Turn the tester on.
   4. Select the following menu items: DIAGNOSIS / ENHANCED OBD II / DATA LIST / PRIMARY / VEHICLE SPD.
   5. Drive the vehicle.
   6. Read the value displayed on the tester.

      OK: 

      Vehicle speeds displayed on tester and speedometer display are equal. 

   NG: CHECK INTERMITTENT PROBLEMS 

   OK: Go to Next Step 

3. CHECK COMBINATION METER ASSEMBLY (+S VOLTAGE) 
   1. Disconnect the E20 combination meter connector.
   2. Turn the engine switch on (IG).
   3. Measure the voltage between the specified terminal of the combination meter and body ground.

      Standard voltage 

      VOLTAGE SPECIFICATION
      
      

      Tester Connection	Specified Condition
      E20-12 (+S) - Body ground	4.5 to 5.5 V

      Fig 1: Identifying E20 Combination Meter Connector Terminals

      Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   4. Reconnect the combination meter connector.

   NG: Go to step   5 

   OK: Go to next step 

4. CHECK COMBINATION METER ASSEMBLY (SPD SIGNAL WAVEFORM) 
   1. Shift the transmission gear selector lever to the neutral position.
   2. Jack up the vehicle.
   3. Turn the engine switch on (IG).
   4. Measure the voltage between the specified terminal of the combination meter and body ground while the wheel is turned slowly.

      Standard voltage 

      VOLTAGE SPECIFICATION
      
      

      Tester Connection	Specified Condition
      E20-12 (+S) - Body ground	Voltage generated intermittently

      Fig 2: Identifying Combination Meter Connector

      Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      HINT:

      The output voltage should fluctuate up and down, similarly to the diagram, when the wheel is turned slowly.

   NG: REPLACE COMBINATION METER ASSEMBLY  (See REMOVAL )

   OK: Go to Next Step 

5. CHECK HARNESS AND CONNECTOR (COMBINATION METER ASSEMBLY - ECM) 
   1. Disconnect the E20 combination meter connector.
   2. Disconnect the A10 ECM connector.
   3. Measure the resistance.

      Standard resistance (Check for open) 

      RESISTANCE REFERENCE (CHECK FOR OPEN)
      
      

      Tester Connection	Specified Condition
      +S (E20-12) - SPD (A10-8)	Below 1 Ω

      Standard resistance (Check for short) 

      RESISTANCE REFERENCE (CHECK FOR SHORT)
      
      

      Tester Connection	Specified Condition
      +S (E20-12) or SPD (A10-8) - Body ground	10 kΩ or higher

      Fig 3: Identifying A10 ECM Connector Terminals & E20 Combination Meter Connector Terminals

      Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   4. Reconnect the combination meter connector.
   5. Reconnect the ECM connector.

   NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

   OK: REPLACE ECM (See  REMOVAL  )