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Inspection Procedure

NOTE: Inspect the fuses of circuits related to this system before performing the following inspection procedure.

CHECK THAT MIL IS ILLUMINATED

Check the MIL illumination condition.

MIL CONDITION CHART

MIL Condition	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 the Techstream to the DLC3.
2. Turn the ignition switch to ON.
3. Turn the Techstream on.
4. Enter the following menus: Powertrain / Engine and ECT / Trouble Codes.
5. Check if any DTCs are output. Note down any DTCs.
  HINT:
  
  Check for DTCs output from other ECUs which relate to the MIL.
6. Clear the DTCs (See DTC CHECK / CLEAR ).
7. Check if the MIL turns off.
  OK: MIL turns off.
  
  NG: Go to step 3
  
  OK: REPAIR CIRCUITS INDICATED BY OUTPUT DTCS (See DIAGNOSTIC TROUBLE CODE CHART )
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.
  NG: Go to step 4
  
  Fig 1: Identifying A9 ECM Connector
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  
  OK: REPLACE ECM (See REMOVAL )

CHECK HARNESS AND CONNECTOR (COMBINATION METER - ECM)

Disconnect the ECM connector.
Disconnect the combination meter connector.

Measure the resistance according to the value(s) in the table below.

Standard Resistance (Check for short)

TESTER CONNECTION SPECIFIED CONDITION CHART

Tester Connection	Condition	Specified Condition
A9-36(W) or E19-8(EFI) - Body ground	Always	10 kΩ or higher

Reconnect the ECM connector.
Reconnect the combination meter connector.
NG: REPAIR OR REPLACE HARNESS OR CONNECTOR

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

OK: REPLACE COMBINATION METER ASSEMBLY (See REMOVAL )

CHECK THAT MIL IS ILLUMINATED
1. Check if the MIL is illuminated when the ignition switch is turned to ON.
  OK: MIL is illuminated.
  
  NG: Go to step 6
  
  OK: SYSTEM OK

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: *: The Techstream cannot communicate with the ECM.

B: GO TO VC OUTPUT CIRCUIT (See )

A: Go to Next Step

CHECK HARNESS AND CONNECTOR (COMBINATION METER - ECM)

Disconnect the ECM connector.
Disconnect the combination meter connector.

Measure the resistance according to the value(s) in the table below.

Standard Resistance (Check for open)

TESTER CONNECTION SPECIFIED CONDITION CHART

Tester Connection	Condition	Specified Condition
A9-36 (W) - E19-8 (EFI)	Always	Below 1 Ω

Reconnect the ECM connector.
Reconnect the combination meter connector.
NG: REPAIR OR REPLACE HARNESS OR CONNECTOR

Fig 3: Identifying Combination Meter Connector And ECM Connector
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

OK: REPLACE COMBINATION METER (See REMOVAL )