Lighting

Ignition Switch Circuit

3steps
~18min
2/5difficulty
Done 0 of 3

DESCRIPTION

The Multiplex network body ECU receives the ACC and IG signals from the ignition switch.

WIRING DIAGRAM

WIRING DIAGRAM

INSPECTION PROCEDURE

1 READ VALUE OF INTELLIGENT TESTER

  1. Connect the intelligent tester to DLC3.
  2. Turn the ignition switch ON and push the intelligent tester main switch ON.
  3. Select the items below in the DATA LIST, and read the displays on the intelligent tester.

BODY NO.1:

BODY NO.1

2 INSPECT FUSE

  1. Inspect the ECU ACC fuse, ECU-IG fuse and AM1 fuse in instrument panel junction block assembly.

3 INSPECT RELAY

INSPECT RELAY
  1. Inspect ACC relay continuity.

Resistance

Resistance
INSPECT RELAY
  1. Inspect IG1 relay continuity.

Resistance

Resistance

4 INSPECT INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY (ACC, IG)

  1. Measure the voltage between the terminals as shown in the chart below.

Voltage

Voltage
INSPECT INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY (ACC, IG)

5 INSPECT INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY (+B)

  1. Measure voltage between the terminal 1A-1 of the instrument panel junction block assembly and body ground.

Voltage

Voltage
INSPECT INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY (+B)

6 INSPECT INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY

  1. Measure voltage between the terminal 1H-10 of the instrument panel junction block assembly and body ground.

Voltage

Voltage
INSPECT INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY

REPAIR OR REPLACE HARNESS OR CONNECTOR

Test yourself

A quick Toyota Sienna quiz: every answer comes with an explanation and a link to the manual page.