DESCRIPTION
Illumination of the front fog lights is controlled by the main body ECU (multiplex network body ECU).
WIRING DIAGRAM
CAUTION / NOTICE / HINT
Note
Inspect the fuses for circuits related to this system before performing the following inspection procedure.
Before performing troubleshooting, check that the taillight circuit operates properly.
If the main body ECU (multiplex network body ECU) is replaced, refer to the Service Bulletin.
As the door control battery is installed between the vehicle battery and main body ECU (multiplex network body ECU), first perform the inspections in On-Vehicle Inspection to confirm that there are no malfunctions in the power source circuit for the main body ECU (multiplex network body ECU) before performing this troubleshooting procedure.
PROCEDURE
PERFORM ACTIVE TEST USING GTS (FRONT FOG LIGHT RELAY)
Using the GTS, perform the Active Test.
| Tester Display | Measurement Item | Control Range | Diagnostic Note |
|---|---|---|---|
| Front Fog Light Relay | Front fog light relay | ON or OFF | The headlight dimmer switch (light control switch) is in the tail position. |
| Tester Display |
|---|
| Front Fog Light Relay |
Tech Tips
Check the operation with the taillights illuminated.
| Result | ||||||
|---|---|---|---|---|---|---|
|
| A |
|
PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE Click here |
| B |
|
CHECK NO. 1 INTEGRATION RELAY (FR FOG RELAY)
Remove the No. 1 integration relay.
Inspect the fog light relay.
| Result | |||
|---|---|---|---|
|
| NG |
|
REPLACE NO. 1 INTEGRATION RELAY Click here |
| OK |
|
CHECK HARNESS AND CONNECTOR (NO. 1 INTEGRATION RELAY - BATTERY)
| *a | Front view of wire harness connector (to No. 1 Integration Relay) |
Disconnect the No. 1 integration relay connector.
Measure the voltage according to the value(s) in the table below.
| Standard Voltage | ||||||
|---|---|---|---|---|---|---|
|
| Result | |||
|---|---|---|---|
|
| NG |
|
REPAIR OR REPLACE HARNESS OR CONNECTOR |
| OK |
|
CHECK HARNESS AND CONNECTOR (TAILLIGHT RELAY [TAIL RELAY] - NO. 1 INTEGRATION RELAY)
| *a | Front view of wire harness connector (to No. 1 Integration Relay) |
Disconnect the No. 1 integration relay connector.
Measure the voltage according to the value(s) in the table below.
| Standard Voltage | ||||||
|---|---|---|---|---|---|---|
|
| Result | |||
|---|---|---|---|
|
| NG |
|
CHECK HARNESS AND CONNECTOR (NO. 1 INTEGRATION RELAY - JUNCTION BLOCK ASSEMBLY LH) Click here |
| OK |
|
CHECK HARNESS AND CONNECTOR (NO. 1 INTEGRATION RELAY - FOG LIGHT ASSEMBLY RH)
Disconnect the 1C No. 1 integration relay connector.
Disconnect the C1 fog light assembly RH connector.
Measure the resistance according to the value(s) in the table below.
| Standard Resistance | |||||||||
|---|---|---|---|---|---|---|---|---|---|
|
|||||||||
|
| Result | |||
|---|---|---|---|
|
| NG |
|
REPAIR OR REPLACE HARNESS OR CONNECTOR |
| OK |
|
CHECK HARNESS AND CONNECTOR (NO. 1 INTEGRATION RELAY - MAIN BODY ECU [MULTIPLEX NETWORK BODY ECU])
Disconnect the 1C No. 1 integration relay connector.
Remove the main body ECU (multiplex network body ECU) from the junction block assembly LH.
Connect the 4F junction block assembly LH connector.
Measure the resistance according to the value(s) in the table below.
| Standard Resistance | |||||||||
|---|---|---|---|---|---|---|---|---|---|
|
| Result | |||
|---|---|---|---|
|
| OK |
|
REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU) Click here |
| NG |
|
CHECK HARNESS AND CONNECTOR (NO. 1 INTEGRATION RELAY - JUNCTION BLOCK ASSEMBLY LH) Click here |
CHECK HARNESS AND CONNECTOR (NO. 1 INTEGRATION RELAY - JUNCTION BLOCK ASSEMBLY LH)
Disconnect the 1C No. 1 integration relay connector.
Disconnect the 4F junction block assembly LH connector.
Measure the resistance according to the value(s) in the table below.
| Standard Resistance | |||||||||
|---|---|---|---|---|---|---|---|---|---|
|
| Result | |||
|---|---|---|---|
|
| OK |
|
REPLACE JUNCTION BLOCK ASSEMBLY LH Click here |
| NG |
|
REPAIR OR REPLACE HARNESS OR CONNECTOR |
CHECK HARNESS AND CONNECTOR (NO. 1 INTEGRATION RELAY - JUNCTION BLOCK ASSEMBLY LH)
Disconnect the 1C No. 1 integration relay connector.
Disconnect the 4F junction block assembly LH connector.
Measure the resistance according to the value(s) in the table below.
| Standard Resistance | |||||||||
|---|---|---|---|---|---|---|---|---|---|
|
| Result | |||
|---|---|---|---|
|
| OK |
|
REPLACE JUNCTION BLOCK ASSEMBLY LH Click here |
| NG |
|
REPAIR OR REPLACE HARNESS OR CONNECTOR |