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Inspection Procedure

CHECK MIL
1. Check that the MIL lights up when turning the ignition switch ON.
OK:

MIL lights up

OK: SYSTEM OK

NG: Go to next step

CHECK CONNECTION BETWEEN TECHSTREAM AND ECM

Connect the Techstream to the DLC3.
Turn the ignition switch ON and tester ON.
Check the communication between the Techstream and ECM.

Result

RESULT CHART

Condition	Proceed to
Communication is not possible	A
Communication is possible	B

B: GO TO MIL CIRCUIT

A: Go to next step

CHECK ECM (VC VOLTAGE)
1. Turn the ignition switch ON.
2. Measure the voltage of the ECM connector.
Result:

Voltage is not 5 V

Fig 1: Checking ECM (VC Voltage)
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

CHECK MIL (THROTTLE POSITION SENSOR)

Disconnect the T26 throttle body connector.
Turn the ignition switch ON.
Check the MIL.

Result

RESULT CHART

Condition	Proceed to
MIL does not illuminate	A
MIL Illuminates	B

B: REPLACE THROTTLE BODY ASSEMBLY

A: Go to next step

CHECK MIL (CANISTER PUMP MODULE)

Disconnect the C12 canister pump module connector.
Turn the ignition switch ON.
Check the MIL.

Result

RESULT CHART

Condition	Proceed to
MIL does not Illuminate	A
MIL Illuminates	B

B: REPLACE CANISTER

A: Go to next step

CHECK WIRE HARNESS (ECM - BODY GROUND)

Disconnect the T26 throttle body connector.
Disconnect the C12 canister pump module connector.
Disconnect the E2 ECM connector.
Measure the resistance of the wire harness connector.

Standard resistance

TESTER CONNECTION SPECIFIED CONDITION CHART

Tester Connection	Specified Condition
E2-29 (VC) - Body ground	10 kΩ or higher

NG: REPAIR OR REPLACE HARNESS AND CONNECTOR

Fig 2: Disconnecting E2 ECM Connector

G05291547

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

OK: REPLACE ECM