Inspection Procedure

1. Connect the hand-held tester to the DLC3.
2. Turn the ignition switch to the ON position and turn the hand-held tester main switch on.
3. Select the item below in the ACTIVE TEST and then check the relay operation.

BODY NO.5 (MULTIPLEX NETWORK FRONT LIGHT ECU): 

Fig 1: Diagnostic Chart (Multiplex Network Front Light ECU)

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OK: Front fog lamp comes on. 

1. NG: Go to step 2 
2. OK: PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE (SEE  PROBLEM SYMPTOMS TABLE  ) 

1. Remove the FOG relay from the engine room No.2 R/B.
   Fig 2: Locating Fog Relay Connected To Engine Room No.2 R/B

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2. Inspect the FOG relay continuity.

1. Measure the resistance according to the value (s) in the figure Fig 3 below.

Standard: 

Fig 3: Standard Resistance Reference Chart

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1. NG: REPLACE RELAY 
   Fig 4: Inspecting Fog Relay Continuity

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2. OK: Go to Next Step. 

1. Using a service wire, connect R5 and R6 in the engine room No.2 R/B.

OK: Fog lamp comes on. 

1. NG: Go to step   5 
   Fig 5: Inspecting Multiplex Network Body ECU (Engine Room No.2 R/B)

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2. OK: Go to Next Step. 

1. Disconnect 2-3 connector from the engine room No. R/B.
2. Remove the front light ECU from the engine room No.2 R/B.
   Fig 6: Identifying Connector Terminals Of Engine Room No.2 R/B (Connector Front View)

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3. Using a service wire, connect R7 and R8 in the engine room No.2 R/B.
4. Measure the resistance according to the value (s) in the figure Fig 7 below.

Standard: 

Fig 7: Resistance Reference Chart

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1. NG: REPLACE MULTIPLEX NETWORK BODY ECU (ENGINE ROOM No.2 R/B) 
   Fig 8: Identifying Connector Terminals Of Engine Room No.2 R/B (Relay Side View)

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2. OK: PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE (SEE  PROBLEM SYMPTOMS TABLE  ) 

1. Measure the voltage according to the value (s) in the figure Fig 9 below.

HINT:

Inspect the side suspected malfunctioning part is on.

Standard: 

Fig 9: Tester Connection Reference Chart

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1. NG: Go to step 6 
   Fig 10: Inspecting Multiplex Network Body ECU (Engine Room No.2 R/B)

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2. OK: REPAIR OR REPLACE HARNESS OR CONNECTOR (EACH OF FOG LAMP CIRCUIT) 

1. Disconnect 2-3 connector from the engine room No.2 R/B.
2. Measure the voltage according to the value (s) in the figure Fig 11 below.

Standard: 

Fig 11: Voltage Reference Chart

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1. NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 
   Fig 12: Checking Harness And Connector (Power Source Circuit)

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2. OK: Go to Next Step. 

1. Remove the front light ECU from the engine room No.2 R/B.
2. Using a service wire, connect R7 and R8 of the engine room No.2 R/B.
3. Measure the resistance according to the value (s) in the figure Fig 13 below.

Standard: 

Fig 13: Resistance Reference Chart

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1. NG: REPLACE MULTIPLEX NETWORK BODY ECU (ENGINE ROOM No.2 R/B) 
   Fig 14: Inspecting Multiplex Network Body ECU (Engine Room No.2 R/B)

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2. OK: PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE (SEE  PROBLEM SYMPTOMS TABLE  )