This circuit detects the ignition switch ACC or off condition, and sends it to the main body ECU (multiplex network body ECU).
Inspect the fuses for circuits related to this system before performing the following procedure.
First, check for smart entry and start system (for Start Function) DTCs, and after confirming that there is no malfunction, proceed with troubleshooting.*
Before replacing the main body ECU (multiplex network body ECU), refer to Service Bulletin.*
*: w/ Smart Entry and Start System
Connect the GTS to the DLC3.
Turn the ignition switch to ON.
Turn the GTS on.
Enter the following menus: Body Electrical / Main Body / Data List.
Read the Data List according to the display on the GTS.
| Tester Display | Measurement Item | Range | Normal Condition | Diagnostic Note |
|---|---|---|---|---|
| ACC SW | Ignition switch ACC signal | OFF or ON | OFF: Ignition switch off
ON: Ignition switch ACC |
"ON" is also displayed for this item when the ignition switch is ON. |
| Tester Display |
|---|
| ACC SW |
Normal conditions listed above are displayed.
| Proceed to |
|---|
| OK |
| NG |
OK
NG
Disconnect the 4D and 4F driver side junction block assembly connectors.
Measure the voltage according to the value(s) in the table below.
| Tester Connection | Condition | Specified Condition |
|---|---|---|
| 4D-1 - Body ground | Always | 11 to 14 V |
Measure the resistance according to the value(s) in the table below.
| Tester Connection | Condition | Specified Condition |
|---|---|---|
| 4F-3 - Body ground | Always | Below 1 Ω |
| Proceed to |
|---|
| OK |
| NG |
OK
NG
Disconnect the I86 main body ECU (multiplex network body ECU) connector.
Measure the resistance according to the value(s) in the table below.
| Tester Connection | Condition | Specified Condition |
|---|---|---|
| I86-19 (GND2) - Body ground | Always | Below 1 Ω |
| Proceed to |
|---|
| OK |
| NG |
OK
NG
| *a | Component with harness connected
(Driver Side Junction Block Assembly) |
- | - |
Connect the 4D and 4F driver side junction block assembly connectors.
Connect the I86 main body ECU (multiplex network body ECU) connector.
Measure the voltage according to the value(s) in the table below.
| Tester Connection | Condition | Specified Condition |
|---|---|---|
| 4E-30 - Body ground | Ignition switch ACC | 11 to 14 V |
| Proceed to |
|---|
| OK |
| NG |
OK
NG
| *a | Component without harness connected
(Driver Side Junction Block Assembly) |
- | - |
Remove the main body ECU (multiplex network body ECU) from the driver side junction block assembly.
Measure the resistance according to the value(s) in the table below.
| Tester Connection | Condition | Specified Condition |
|---|---|---|
| 4F-3 - MB-11 (GND1) | Always | Below 1 Ω |
| 4D-1 - MB-30 (ACC) | Battery not connected to 4E-30 and 4F-3 | 10 kΩ or higher |
| 4D-1 - MB-30 (ACC) | Battery positive (+) → 4E-30
Battery negative (-) → 4F-3 |
Below 1 Ω |
| Proceed to |
|---|
| OK |
| NG |
OK
NG