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Inspection Procedure

CHECK THAT MIL IS ILLUMINATED

Perform troubleshooting in accordance with the table below:

Result

RESULT CHART

Conditions	Proceed to
MIL remains ON	A
MIL does not illuminate	B

B: Go to step 5

A: Go to next step

CHECK WHETHER MIL TURNS OFF
1. Connect Techstream to the DLC3.
2. Turn the ignition switch to ON and turn the tester on.
3. Select the following menu items: Powertrain/Engine/Trouble Codes.
4. Check if any DTCs have been stored. Note down any DTCs.
5. Clear the DTCs (See DTC CHECK/CLEAR ).
6. Check if the MIL goes off.
  Standard:
  
  MIL goes off.
  
  OK: REPAIR CIRCUITS INDICATED BY OUTPUT DTCS (See DIAGNOSTIC TROUBLE CODE CHART )
  
  NG: Go to next step
CHECK HARNESS AND CONNECTOR (CHECK FOR SHORT IN WIRE HARNESS)
1. Disconnect the ECM connector.
2. Turn the ignition switch to ON.
3. Check that the MIL is not illuminated.
  OK:
  
  MIL is not illuminated.
4. Reconnect the ECM connector.
  OK: REPLACE ECM (See REMOVAL )
  
  Fig 1: Identifying Terminal W Of A55 ECM Connector
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  
  NG: Go to next step

CHECK HARNESS AND CONNECTOR (COMBINATION METER - ECM)

Disconnect the ECM connector.
Disconnect the combination meter connector.

Measure the resistance.

Standard resistance (Check for short)

RESISTANCE SPECIFIED CONDITIONS

Tester Connection	Specified Condition
A55-24 (W) or E3-9 (CHK) - Body ground	10 kΩ or higher

Reconnect the ECM connector.
Reconnect the combination meter connector.
OK: REPAIR OR REPLACE COMBINATION METER ASSEMBLY

Fig 2: Identifying E3 Combination Meter And A55 ECM Connector Terminals
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

NG: REPAIR OR REPLACE HARNESS OR CONNECTOR

CHECK THAT MIL IS ILLUMINATED
1. Check if the MIL is illuminated when the ignition switch is turned to ON.
  OK:
  
  MIL is illuminated.
  
  OK: SYSTEM OK
  
  NG: Go to next step

CHECK THAT ENGINE STARTS

Turn the ignition switch to ON.

Start the engine.

Result

RESULT CHART

Result	Proceed to
Engine starts	A
Engine does not start*	B
HINT: *: Techstream cannot communicate with the ECM.

B: GO TO VC OUTPUT CIRCUIT

A: Go to next step

INSPECT COMBINATION METER ASSEMBLY (MIL CIRCUIT)
1. Check the MIL circuit (See PROBLEM SYMPTOMS TABLE ).
  NG: REPAIR OR REPLACE COMBINATION METER ASSEMBLY
  
  OK: CHECK AND REPLACE HARNESS AND CONNECTOR (COMBINATION METER - ECM)