Ignition Switch Circuit

LIGHTING SYSTEM: Ignition Switch Circuit

Ignition Switch Circuit

DESCRIPTION

This circuit detects the state of the ignition switch and sends it to the body ECU.

WIRING DIAGRAM





INSPECTION PROCEDURE

PROCEDURE

1. READ VALUE OF TECHSTREAM
(a) Connect the Techstream to the DLC3.
(b) Turn the ignition switch to ON.
(c) Turn the Techstream on.
(d) Enter the following menus: Body Electrical / Body / Data List.
(e) Read the display on Techstream.

Body (Body ECU)





OK:
Normal conditions listed above are displayed.
NG -- INSPECT FUSE
OK -- PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE
2. INSPECT FUSE
(a) Inspect the ECU-ACC fuse, ECU-IG No.1 fuse and AM1 fuse in the instrument panel junction block assembly.
Resistance:
Below 1 Ohms
NG -- REPLACE FUSE
OK -- Continue to next step.
3. INSPECT RELAY





(a) Inspect ACC relay continuity.
(1) Remove the ACC relay from the instrument panel J/B.
(2) Measure the resistance according to the value(s) in the table below.
Resistance:










(b) Inspect IG1 relay continuity.
(1) Remove the IG1 relay from the instrument panel J/B.
(2) Measure the resistance according to the value(s) in the table below.
Resistance:






NG -- REPLACE RELAY
OK -- Continue to next step.
4. INSPECT INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY (ACC, IG)
(a) Measure the voltage according to the value(s) in the table below.





Voltage:






NG -- INSPECT INSTRUMENT PANEL J/B ASSEMBLY (POWER SOURCE CIRCUIT)
OK -- PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE
5. INSPECT INSTRUMENT PANEL J/B ASSEMBLY (POWER SOURCE CIRCUIT)
(a) Measure the voltage according to the value(s) in the table below.





Voltage:






NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR (BATTERY - INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY)
OK -- Continue to next step.
6. INSPECT INSTRUMENT PANEL J/B ASSEMBLY
(a) Measure the voltage according to the value(s) in the table below.





Voltage:






NG -- REPLACE INSTRUMENT PANEL J/B ASSEMBLY
OK -- Continue to next step.
7. CHECK HARNESS AND CONNECTOR (INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY - BODY GROUND)
(a) Disconnect the 1F connector from the instrument panel junction block assembly.
(b) Measure the resistance according to the value(s) in the table below.





Resistance:






NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- Continue to next step.
8. INSPECT IGNITION SWITCH





(a) Disconnect the ignition switch connector.
(b) Measure the resistance according to the value(s) in the table below.
Resistance:






NG -- REPLACE IGNITION SWITCH
OK -- REPAIR OR REPLACE HARNESS OR CONNECTOR (INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY - IGNITION SWITCH)