Inspection Procedure

WARNING: This page is about a different car, the 2006 Toyota Avalon. However, it is still accessible from the selected car via links, so may be relevant.

INSPECT ENGINE SWITCH

Disconnect the D21 switch connector.
Connect the positive (+) lead to terminal "A" and the negative (-) lead to terminal "B" of the engine switch.

Check if the illumination for the engine switch comes on.

OK: Go to Next Step

POSITIVE/NEGATIVE CONNECTION AND ILLUMINATION CONDITION

Positive (+) Connection (Symbols)	Negative (-) Connection (Symbols)	Illumination Condition
D21-11 (SWIL)	D21-4 (COM) or D21-5 (GND)	Comes on
D21-12 (INDS)	D21-4 (COM) or D21-5 (GND)	Comes on
D21-13 (INDW)	D21-4 (COM) or D21-5 (GND)	Comes on

NG: REPLACE ENGINE SWITCH

Fig 1: Identifying Engine Switch Connector

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

OK: Go to Next Step

CHECK WIRE HARNESS (ENGINE SWITCH - POWER SOURCE CONTROL ECU AND BODY GROUND)

Disconnect the D44 ECU connector.

Fig 2: Disconnecting D44 ECU Connector
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

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

Resistance

Fig 3: Identifying Engine Switch Connector

CONNECTOR TERMINALS RESISTANCE SPECIFICATION

Tester Connection (Symbols)	Condition	Specified condition
D44-4 (INDS) - D21-12 (INDS)	Always	Below 1 Ω
D44-13 (INDW) - D21-13 (INDW)	Always	Below 1 Ω
D44-36 (SWIL) - D21-11 (SWIL)	Always	Below 1 Ω
D44-4 (INDS) - Body ground	Always	1 MΩ or Higher
D44-13 (INDW) - Body ground	Always	1 MΩ or Higher
D44-36 (SWIL) - Body ground	Always	1 MΩ or Higher

NG: REPAIR OR REPLACE HARNESS OR CONNECTOR

OK: REPLACE POWER SOURCE CONTROL ECU