Interior Light Circuit
LIGHTING: LIGHTING SYSTEM: Interior Light Circuit
Interior Light Circuit
DESCRIPTION
The Interior lights turn on when a door is opened, and turn off when the door is closed. This illumination setting can be canceled using the overhead J/B switch.
In addition, the interior lights blink while the theft deterrent system is sounding an alarm.
The turning on and off of the interior lights is controlled by the main body ECU LH based on various signals received through BEAN communication.
The main body ECU LH includes a MOS-FET (Metal Oxide Semiconductor - Field Effect Transistor) circuit that fades the interior lights in and out by duty control.
This MOS-FET circuit has an overheat protection function as a fail-safe. If the main body ECU LH becomes excessively hot, the interior lights turn off and remain off.
Normal operation will resume when the conditions required to turn on the interior lights are met again.
If the vehicle is equipped with scuff plate lights, their operation timing is the same as that of the interior lights.
WIRING DIAGRAM
INSPECTION PROCEDURE
PROCEDURE
1. CHECK SEAT ILLUMINATION (OPERATION)
HINT:
The personal lights and interior lights share the same power source. Therefore, if none of them come on, inspect the power source circuit first.
(a) Push the switches for the personal lights.
(b) Check that the personal lights come on.
OK:
Personal lights come on.
NG -- CHECK HARNESS AND CONNECTOR (POWER SOURCE)
OK -- Continue to next step.
2. PERFORM ACTIVE TEST USING TECHSTREAM
(a) Connect the Techstream to the DLC3.
(b) Turn the engine switch on (IG).
(c) Turn the Techstream on.
(d) Enter the following menus: Body Electrical / Body No. 3 / Active Test.
(e) Check the operation.
Body No. 3 (Main Body ECU LH)
OK:
The front and rear interior lights come on.
Result:
C -- CHECK HARNESS AND CONNECTOR (MAIN BODY ECU LH - OVERHEAD J/B)
B -- INSPECT REAR DOME LIGHT ASSEMBLY (REAR INTERIOR LIGHT)
A -- REPLACE MAIN BODY ECU LH (COWL SIDE J/B LH)
D -- PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE
3. INSPECT REAR DOME LIGHT ASSEMBLY (REAR INTERIOR LIGHT)
(a) Remove the rear dome light assembly.
(b) Connect the (+) lead from the battery to terminal 2 and the (-) lead to terminal 4, and then check that the interior light comes on.
OK:
The interior light comes on.
NG -- REPLACE REAR DOME LIGHT ASSEMBLY
OK -- Continue to next step.
4. CHECK HARNESS AND CONNECTOR (OVERHEAD J/B - REAR DOME LIGHT ASSEMBLY)
(a) Disconnect the R8 rear dome light assembly connector.
(b) Disconnect the R5 overhead J/B connector.
(c) Measure the resistance according to the value(s) in the table below.
Standard resistance:
NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- REPLACE MAIN BODY ECU LH (COWL SIDE J/B LH)
5. CHECK HARNESS AND CONNECTOR (MAIN BODY ECU LH - OVERHEAD J/B)
(a) Disconnect the Q1 main body ECU LH connector.
(b) Measure the voltage according to the value(s) in the table below.
Standard voltage:
NG -- CHECK HARNESS AND CONNECTOR (MAIN BODY ECU LH - OVERHEAD J/B)
OK -- REPLACE MAIN BODY ECU LH (COWL SIDE J/B LH)
6. CHECK HARNESS AND CONNECTOR (MAIN BODY ECU LH - OVERHEAD J/B)
(a) Disconnect the Q1 main body ECU LH connector.
(b) Disconnect the R5 overhead J/B connector.
(c) Measure the resistance according to the value(s) in the table below.
Standard resistance:
NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- REPLACE MAIN BODY ECU LH (COWL SIDE J/B LH)
7. CHECK HARNESS AND CONNECTOR (POWER SOURCE)
(a) Disconnect the R5 overhead J/B connector.
(b) Measure the voltage according to the value(s) in the table below.
Standard voltage:
NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- REPLACE MAIN BODY ECU LH (COWL SIDE J/B LH)