DESCRIPTION
The main body ECU (multiplex network body ECU) controls the front fog lights.
WIRING DIAGRAM
CAUTION / NOTICE / HINT
Note
Inspect the fuses for circuits related to this system before performing the following procedure.
Before replacing the main body ECU (multiplex network body ECU), refer to Service Bulletin.
The vehicle battery supplies power to the main body ECU (multiplex network body ECU) via the door control battery. Therefore, before proceeding with troubleshooting, perform an on-vehicle inspection and confirm that the main body ECU (multiplex network body ECU) power source circuit is normal.*
*: w/o Canister Pump Module with Door Ajar Warning Buzzer Function
PROCEDURE
CHECK OPERATION (TAILLIGHTS)
Check the operation of the taillights.
| OK |
|---|
| Taillights operate normally. |
| Result | |||
|---|---|---|---|
|
| NG |
|
GO TO PROBLEM SYMPTOMS TABLE Click here |
| OK |
|
PERFORM ACTIVE TEST USING GTS
Connect the GTS to the DLC3.
Turn the engine switch on (IG).
Turn the GTS on.
Enter the following menus: Body Electrical / Main Body / Active Test.
Perform the Active Test according to the display on the GTS.
| Tester Display | Measurement Item | Control Range | Diagnostic Note |
|---|---|---|---|
| Front Fog Light Relay | Front fog lights | ON/OFF | Light control switch in tail position |
| Tester Display |
|---|
| Front Fog Light Relay |
| OK |
|---|
| Front fog lights come on. |
| Result | |||
|---|---|---|---|
|
| OK |
|
PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE Click here |
| NG |
|
CHECK SEMICONDUCTOR POWER INTEGRATION ECU
Using a voltmeter, check the signal reading of the semiconductor pwr integration ECU.
| OK |
|---|
| Output signal reading is normal. |
| Result | |||
|---|---|---|---|
|
| NG |
|
INSPECT SEMICONDUCTOR POWER INTEGRATION ECU (RESULTS OF SIGNAL READING CHECK) Click here |
| OK |
|
CHECK HARNESS AND CONNECTOR (SEMICONDUCTOR PWR INTEGRATION ECU POWER SOURCE AND BODY GROUND)
Remove the semiconductor pwr integration ECU from the No. 1 engine room relay block and No. 1 junction block assembly.
| *a | Component without semiconductor pwr integration ECU connected (No. 1 Engine Room Relay Block and No. 1 Junction Block Assembly) |
- | - |
Measure the voltage according to the value(s) in the table below.
| Standard Voltage | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
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 (SEMICONDUCTOR PWR INTEGRATION ECU - INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY)
Disconnect the 2C instrument panel junction block assembly connector.
Measure the resistance according to the value(s) in the table below.
| Standard Resistance | |||||||||
|---|---|---|---|---|---|---|---|---|---|
|
| Result | |||
|---|---|---|---|
|
| NG |
|
REPAIR OR REPLACE HARNESS OR CONNECTOR |
| OK |
|
INSPECT INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY
Remove the instrument panel junction block assembly.
Remove the main body ECU (multiplex network body ECU) from the instrument panel junction block assembly.
Measure the resistance according to the value(s) in the table below.
| *a | Component without harness connected (Instrument Panel Junction Block Assembly) |
- | - |
| Standard Resistance | ||||||
|---|---|---|---|---|---|---|
|
| Result | |||
|---|---|---|---|
|
| NG |
|
REPLACE INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY Click here |
| OK |
|
REPLACE SEMICONDUCTOR POWER INTEGRATION ECU
Replace the semiconductor pwr integration ECU with a new or known good one.
Check that the front fog lights operate normally.
| OK |
|---|
| Front fog lights operate normally. |
| Result | |||
|---|---|---|---|
|
| OK |
|
END (SEMICONDUCTOR PWR INTEGRATION ECU WAS DEFECTIVE) |
| NG |
|
REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU) Click here |