LIGHTING (INT) LIGHTING SYSTEM IG Signal Circuit

DESCRIPTION

This circuit detects the ignition switch ON or off condition, and sends it to the main body ECU (multiplex network body ECU).

WIRING DIAGRAM

0.063,1.292 1.271,1.844 1.208,0.552 10 false from Ignition Switch Assembly 0.24,0.677 1.146,0.917 0.906,0.24 10 false from Battery 1.938,0.885 2.396,1.083 0.458,0.198 10 false ALT 3.083,3.073 3.333,3.25 0.25,0.177 10 false 3C 3.083,2.531 3.333,2.708 0.25,0.177 10 false 3D 3.083,1.104 3.333,1.281 0.25,0.177 10 false 3D 3.083,0.708 3.333,0.885 0.25,0.177 10 false 3B 3.083,2.031 3.333,2.208 0.25,0.177 10 false 3C 3.083,1.625 3.333,1.802 0.25,0.177 10 false 3C 5.5,3.865 5.75,4.042 0.25,0.177 10 false MB 3.792,1.385 4.625,1.563 0.833,0.177 10 false IG1 NO. 3 4.698,0.865 5.615,1.094 0.917,0.229 10 false ECU-IG NO. 4 5.896,1.948 6.146,2.125 0.25,0.177 10 false 32 5.896,2.438 6.146,2.615 0.25,0.177 10 false 11 3.115,0.51 3.365,0.688 0.25,0.177 10 false 1 3.094,0.917 3.344,1.094 0.25,0.177 10 false 25 3.083,1.438 3.333,1.615 0.25,0.177 10 false 37 3.083,1.833 3.333,2.01 0.25,0.177 10 false 51 3.083,2.344 3.333,2.521 0.25,0.177 10 false 12 3.125,2.906 3.375,3.083 0.25,0.177 10 false 9 6.167,2.042 6.417,2.219 0.25,0.177 10 false IG 6.167,2.542 6.583,2.708 0.417,0.167 10 false GND1 2.99,3.542 5.729,3.833 2.74,0.292 10 false Instrument Panel Junction Block Assembly 5.5,4.031 7.156,4.448 1.656,0.417 10 false Main Body ECU (Multiplex Network Body ECU)

CAUTION / NOTICE / HINT

NOTICE:: Inspect the fuses for circuits related to this system before performing the following procedure.

PROCEDURE

1.READ VALUE USING GTS

Connect the GTS to the DLC3.

Turn the ignition switch to ON.

Turn the GTS on.

Enter the following menus: Body Electrical / Main Body / Data List.

Read the Data List according to the display on the GTS.

Body Electrical > Main Body > Data List

Tester Display	Measurement Item	Range	Normal Condition	Diagnostic Note
IG SW	Ignition switch ON signal	ON or OFF	ON: Ignition switch ON OFF: Ignition switch off	"OFF" is also displayed for this item when the ignition switch is ACC.

Body Electrical > Main Body > Data List

Tester Display
IG SW

50003 123 30

OK:: Normal conditions listed above are displayed.

Result:

Proceed to
OK
NG

PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE

Click hereVehicle Interior>LIGHTING (INT)>LIGHTING SYSTEM>PROBLEM SYMPTOMS TABLE

2.CHECK HARNESS AND CONNECTOR (BATTERY POWER SOURCE)

Disconnect the 3B instrument panel junction block assembly connector.

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

Standard Voltage:

Tester Connection	Condition	Specified Condition
3B-1 - Body ground	Always	11 to 14 V

Result:

Proceed to
OK
NG

3.CHECK HARNESS AND CONNECTOR (INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY - IG1 NO. 3 RELAY POWER SOURCE AND BODY GROUND)

REPAIR OR REPLACE HARNESS OR CONNECTOR

3.CHECK HARNESS AND CONNECTOR (INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY - IG1 NO. 3 RELAY POWER SOURCE AND BODY GROUND)

Disconnect the 3C and 3D instrument panel junction block assembly connectors.

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

Standard Voltage:

Tester Connection	Condition	Specified Condition
3D-25 - Body ground	Ignition switch ON	11 to 14 V

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

Standard Resistance:

Tester Connection	Condition	Specified Condition
3D-12 - Body ground	Always	Below 1 Ω
3C-9 - Body ground	Always	Below 1 Ω

Result:

Proceed to
OK
NG

4.CHECK HARNESS AND CONNECTOR (INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY - INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY)

REPAIR OR REPLACE HARNESS OR CONNECTOR

4.CHECK HARNESS AND CONNECTOR (INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY - INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY)

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

Standard Resistance:

Tester Connection	Condition	Specified Condition
3C-37 - 3C-51	Always	Below 1 Ω
3C-37 or 3C-51 - Body ground	Always	10 kΩ or higher

Result:

Proceed to
OK
NG

5.INSPECT INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY

REPAIR OR REPLACE HARNESS OR CONNECTOR

5.INSPECT INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY

Remove the instrument panel junction block assembly.

Click herePower Source / Network>POWER DISTRIBUTION>MAIN BODY ECU>REMOVAL

Remove the main body ECU (multiplex network body ECU) from the instrument panel junction block assembly.

Click herePower Source / Network>POWER DISTRIBUTION>MAIN BODY ECU>REMOVAL

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

1.802,0.844 2.104,1.042 0.302,0.198 4.875,0.781 5.177,0.979 0.302,0.198 1.063,2.188 1.365,2.385 0.302,0.198 4.188,2.427 4.49,2.625 0.302,0.198 6.354,3.385 6.24,3 false 3.938,3.396 3.823,3.01 false 1.125,2.208 1.438,2.406 0.313,0.198 10 false 3B 1.854,0.865 2.167,1.063 0.313,0.198 10 false 3C 4.938,0.802 5.25,1 0.313,0.198 10 false 3D 4.229,2.448 4.542,2.646 0.313,0.198 10 false MB 0.354,0.302 0.76,0.656 0.406,0.354 10 false *a 6.323,3.427 6.781,3.625 0.458,0.198 10 false IG 3.823,3.427 4.281,3.625 0.458,0.198 10 false GND1

Component without harness connected
(Instrument Panel Junction Block Assembly)

Standard Resistance:

Tester Connection	Condition	Specified Condition
3B-1 - 3C-37	Battery not connected to 3D-25 and 3D-12	10 kΩ or higher
3B-1 - 3C-37	Battery not connected to 3D-25 and 3C-9	10 kΩ or higher
3B-1 - 3C-37	Battery not connected to 3D-25 and MB-11 (GND1)	10 kΩ or higher
3B-1 - 3C-37	Battery positive (+) → 3D-25 Battery negative (-) → 3D-12	Below 1 Ω
3B-1 - 3C-37	Battery positive (+) → 3D-25 Battery negative (-) → 3C-9	Below 1 Ω
3B-1 - 3C-37	Battery positive (+) → 3D-25 Battery negative (-) → MB-11 (GND1)	Below 1 Ω
3C-51 - MB-32 (IG)	Always	Below 1 Ω

Result:

Proceed to
OK
NG

REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU)

Click herePower Source / Network>POWER DISTRIBUTION>MAIN BODY ECU>REMOVAL

REPLACE INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY

Click herePower Source / Network>POWER DISTRIBUTION>MAIN BODY ECU>REMOVAL