Inspection Procedure

WARNING: This page is about a different car, the 2007 Lexus SC 430. However, it is still accessible from the selected car via links, so may be relevant.

CHECK ECM (LCKI VOLTAGE)

Remove the ECM but do not disconnect the connector.
Start the engine and push the AUTO switch.

Measure the voltage of the connector.

Standard voltage

TESTER CONNECTION SPECIFIED CONDITION CHART

Tester Connection	Specified Condition
E2-10 (LCKI) - Body ground	10 to 14 V

Result

RESULT CHART

Result	Proceed to
NG	A
OK (When troubleshooting according to Problem Symptoms Table)	B
OK (When troubleshooting according to DTC Chart)	C

Fig 1: Identifying Connector Terminals Of ECM

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

B: PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE

C: REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY

A: Go to next step.

INSPECT MAGNET CLUTCH ASSEMBLY (LOCK SENSOR)

Disconnect the A2 clutch connector.

Fig 2: Identifying A2 Clutch Connector
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Measure the resistance of the clutch.

Standard resistance

TESTER CONNECTION SPECIFIED CONDITION CHART

Tester Connection	Condition	Specified Condition
1 - 2	20°C (68°F)	990 to 1,210 Ω
1 - 2	100°C (212°F)	1,280 to 1,550 Ω

NG: REPLACE MAGNET CLUTCH ASSEMBLY (LOCK SENSOR)

OK: Go to next step.

CHECK WIRE HARNESS (MAGNET CLUTCH - ECM AND BODY GROUND)

Disconnect the A2 clutch connector.
Disconnect the E2 ECM connector.

Fig 3: Identifying A2 Clutch Connector And E2 ECM Connector
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Measure the resistance of the wire harness side connectors.

Standard resistance

TESTER CONNECTION SPECIFIED CONDITION CHART

Tester Connection	Specified Condition
A2-1 - E2-10 (LCKI)	Below 1 Ω
A2-2 - Body ground	Below 1 Ω

NG: REPAIR OR REPLACE HARNESS OR CONNECTOR

OK: REPLACE ECM