DESCRIPTION
This circuit detects whether the engine switch is on (ACC) or off, and sends this information to 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 procedure.
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.
First, check for smart entry and start system (for Start Function) DTCs, and after confirming that there is no malfunction, proceed with troubleshooting.
PROCEDURE
READ VALUE USING GTS (ACC SW)
Using the GTS, read the Data List.
| Tester Display | Measurement Item | Range | Normal Condition | Diagnostic Note |
|---|---|---|---|---|
| ACC SW | Engine switch on (ACC) signal | ON or OFF | ON: Engine switch on (ACC) OFF: Engine switch off |
"ON" is also displayed for this item when the engine switch is on (IG). |
| Tester Display |
|---|
| ACC SW |
| OK |
|---|
| The display is as specified in the normal condition column. |
| Result | |||
|---|---|---|---|
|
| OK |
|
PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE Click here |
| NG |
|
CHECK HARNESS AND CONNECTOR (JUNCTION BLOCK ASSEMBLY LH - BATTERY AND BODY GROUND)
| *a | Front view of wire harness connector (to Junction Block Assembly LH) |
Disconnect the junction block assembly LH connectors.
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 JUNCTION BLOCK ASSEMBLY LH (ACC RELAY)
| *a | Component without harness connected (Junction Block Assembly LH) |
Remove the junction block assembly LH connectors.
Remove the main body ECU (multiplex network body ECU) from the junction block assembly LH.
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 |
|
REPLACE JUNCTION BLOCK ASSEMBLY LH Click here |