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Interior Room Lamp Control Circuit




INTERIOR ROOM LAMP CONTROL CIRCUIT

Description

Controls each interior room lamp (ground side) by PWM signal.
NOTE:
PWM signal control period is approximately 250 Hz (in the gradual brightening/dimming).


Component Function Check


CAUTION:
Before performing the diagnosis, check that the following is normal.
- Interior room lamp power supply
- Map lamp bulb
- Personal lamp bulb
- Foot lamp bulb

1. CHECK INTERIOR ROOM LAMP CONTROL FUNCTION

CONSULT ACTIVE TEST
1.Switch the map lamp switch to DOOR.
2.Turn ignition switch ON.
3.Select "INT LAMP" of BCM (INT LAMP) active test item.
4.With operating the test items, check that each interior room lamp turns ON/OFF (gradual brightening/dimming).
On: Interior room lamp gradual brightening


Off: Interior room lamp gradual dimming
Does the interior room lamp turns ON/OFF (gradual brightening/dimming)?
YES- Interior room lamp control circuit is normal.
NO- Refer to "Diagnosis Procedure" .


Diagnosis Procedure


1. CHECK INTERIOR ROOM LAMP CONTROL OUTPUT

CONSULT ACTIVE TEST
1.Turn ignition switch OFF.
2.Remove all the bulbs of map lamp, foot lamp and personal lamp.
3.Select "INT LAMP" of BCM (INT LAMP) active test item.
4. With operating the test item, check continuity between BCM harness connector and ground.





Is the measurement value normal?
YES- GO TO 2.
Fixed ON-GO TO 3.
Fixed OFF-Replace BCM. Refer to "Removal and Installation" Removal and Installation.

2. CHECK INTERIOR ROOM LAMP CONTROL OPEN CIRCUIT

1.Turn ignition switch OFF.
2.Disconnect BCM connector, roof module connector and foot lamp connector.
3.Check continuity between BCM harness connector, roof module harness connector, and foot lamp harness connector.





Does continuity exist?
YES- Replace the roof module or the foot lamp.
NO- Repair the harnesses or connectors.

3. CHECK INTERIOR ROOM LAMP CONTROL SHORT CIRCUIT

1.Turn ignition switch OFF.
2.Disconnect BCM connector, roof module connector and foot lamp connector.
3.Check continuity between BCM harness connector and ground.





Does continuity exist?
YES- Repair the harnesses or connectors.
NO- Replace BCM. Refer to "Removal and Installation" Removal and Installation.