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Check Interior Light System

Trouble symptom: 

Spot map lights and reading lights do not turn on/off in accordance with door open/close operations.

Luggage room light does not turn on/off in accordance with rear gate open/close operations.

  1. CHECK INTERIOR LIGHT ILLUMINATION. 
    1. Turn the spot map light switch and the luggage room light switch to the DOOR position.
    2. Open the side doors and the rear gate.
  2. CHECK THE LIGHTS. 

    Check the spot map light, reading light and luggage room light.

    Are the spot map light, reading light and luggage room light normal?

    Yes  Go to  3.

    No  Replace the spot map light, reading light and luggage room light.

  3. CHECK CURRENT DATA. 
    1. Turn the ignition switch to ON.
    2. Display the data of [Driver's door SW input], [P-door SW input], [Rear right door SW input], [Rear left door SW input] and [R Gate SW input] using Subaru Select Monitor. Ref. to DATA MONITOR .

      Does the display switch between [OFF] ↔ [ON] when each side door or rear gate is opened/closed?

      Yes  Go to  5.

      No  Go to  4

  4. CHECK SWITCH. 

    Check the door switch or rear gate latch switch.

    Is the door switch or the rear gate latch switch normal?

    Yes  Go to  5

    No  Replace the door switch or rear gate latch switch.

  5. CHECK HARNESS. 
    1. Disconnect the connectors between body integrated unit and door switch and between body integrated unit and rear gate latch switch.
    2. Check the harnesses between body integrated unit and door switch and between body integrated unit and rear gate latch switch.

      3. Connector & terminal 

      (i171) No. 39 - (R9) No. 2:

      (i171) No. 13 - (R12) No. 2:

      (i171) No. 14 - (R22) No. 2:

      (i171) No. 27 - (R16) No. 2:

      (i171) No. 15 - (D46) No. 3:

      Is harness normal?

      Yes  Go to  6.

      No  Repair or replace the harness.

  6. CHECK HARNESS. 

    Check the harnesses between the connectors of the door switch and rear gate latch switch and the chassis ground.

    Connector & terminal 

    (R9) No. 1 - Chassis ground:

    (R12) No. 1 - Chassis ground:

    (R22) No. 1 - Chassis ground:

    (R16) No. 1 - Chassis ground:

    (D46) No. 4 - Chassis ground:

    Is harness normal?

    Yes  Go to  7.

    No  Repair or replace the harness.

  7. CHECK CURRENT DATA. 
    1. Is harness normal?
    2. Display the data of [Map lamp output] and [Luggage/Trunk lamp output] using Subaru Select Monitor. Ref. to DATA MONITOR .
    • Does the display of [Map lamp output] switch between [OFF] ?? [ON] when the side door is opened/closed?
    • Does the display of [Luggage/Trunk lamp output] switch between [OFF] ?? [ON] when the rear gate is opened/closed?

    Yes  Go to  8

    No  Check the body integrated unit and replace it if defective.

  8. CHECK FUSE AND RELAY. 
    1. Turn the ignition switch to OFF.
    2. Check F/B fuse No. 26 and O/T ILL RELAY. Ref. to Relay and Fuse .

    Is the F/B fuse No. 26 and O/T ILL RELAY normal?

    Yes  Go to  9.

    No  Replace the defective fuse or relay.

  9. CHECK HARNESS. 
    1. Disconnect the connectors of spot map light, reading light, luggage room light and O/T ILL RELAY.
    2. Measure the voltage between each connector and chassis ground.

    Connector & terminal 

    (B225) No. 36 (+) - Chassis ground (-):

    (B225) No. 34 (+) - Chassis ground (-):

    (R405) No. 1 (+) - Chassis ground (-):

    (R369) No. 1 (+) - Chassis ground (-):

    (R370) No. 1 (+) - Chassis ground (-):

    (R371) No. 1 (+) - Chassis ground (-):

    (R372) No. 1 (+) - Chassis ground (-):

    (R141) No. 2 (+) - Chassis ground (-):

    10. Is the voltage 8.5 - 16.5 V?

    Yes  Go to  10.

    No  Repair or replace the harness.

  10. CHECK HARNESS. 
    1. Disconnect the connectors of body integrated unit, spot map light, reading light, luggage room light and O/T ILL RELAY.
    2. Check the harnesses between each light connector and body integrated unit.

    Connector & terminal 

    (i171) No. 11 - (B225) No. 35:

    (i171) No. 10 - (R405) No. 4:

    (i84) No. 9 - (R369) No. 3:

    (i84) No. 9 - (R370) No. 3:

    (i171) No. 16 - (R371) No. 3:

    (i171) No. 16 - (R372) No. 3:

    (i84) No. 8 - (R141) No. 1:

    11. Is harness normal?

    Yes  Go to  11

    No  Repair or replace the harness.

  11. CHECK HARNESS. 

    Check the harnesses between spot map light and reading light connectors and body integrated unit.

    Connector & terminal 

    (R405) No. 13 - Chassis ground:

    (R369) No. 5 - Chassis ground:

    (R370) No. 5 - Chassis ground:

    (R371) No. 5 - Chassis ground:

    (R370) No. 5 - Chassis ground:

    12. Is harness normal?

Yes  Check the body integrated unit and replace it if defective.

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