Toyota Sienna Service Manual: Ignition Switch Circuit

DESCRIPTION

When the ignition switch is turned to the ON position, battery positive voltage is applied to terminal IG of the ECU. When battery positive voltage is applied to terminal IG of the ECU while the theft deterrent system is operating, the warning stops.

WIRING DIAGRAM

INSPECTION PROCEDURE

1 INSPECT FUSES (ECU-IG, AM1)

1. Remove the ECU-IG and AM1 fuses from the instrument panel J/B.
2.  Measure the resistance.

   Standard resistance: Below 1 Ω

2 INSPECT RELAY (IG1)

1. Remove the IG1 relay from the instrument panel J/B.
2.  Check the operation of the IG1 relay.

Standard resistance

3 INSPECT IGNITION OR STARTER SWITCH ASSEMBLY

1. Disconnect the I15 switch connector.
2.  Measure the resistance according to the value(s) in the table below.

Standard resistance

4 CHECK INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY (POWER SOURCE)

1. Disconnect the 1A J/B connector.
2.  Turn the ignition switch ON.
3.  Measure the voltage according to the value(s) in the table below.

Standard voltage

REPLACE INSTRUMENT PANEL J/B ASSEMBLY