CHECK INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY, MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU)
| *A | Main Body ECU (Multiplex Network Body ECU) with 1 connector | *B | Main Body ECU (Multiplex Network Body ECU) with 3 connectors |
| *1 | Main Body ECU (Multiplex Network Body ECU) | - | - |
Remove the main body ECU (multiplex network body ECU) from the instrument panel junction block assembly.
for LHD:
for RHD:
Connect the instrument panel junction block assembly connectors.
Measure the voltage and resistance according to the value(s) in the table below.
| Terminal No. (Symbol) | Wiring Color | Terminal Description | Condition | Specified Condition |
|---|---|---|---|---|
| A-32 (IG) - Body ground | - | Ignition power supply | Ignition switch ON | 11 to 14 V*1 10.5 to 14 V*2 |
| Ignition switch off | Below 1 V | |||
| A-30 (BECU) - Body ground | - | Battery power supply | Always | 11 to 14 V |
| A-29 (ACC) - Body ground | - | ACC power supply | Ignition switch ACC | 11 to 14 V |
| Ignition switch off | Below 1 V | |||
| A-11 (GND1) - Body ground | - | Ground | Always | Below 1 Ω |
*1: w/o Stop and Start System
*2: w/ Stop and Start System
If the result is not as specified, there may be a malfunction in the wire harness or instrument panel junction block assembly.
Install the main body ECU (multiplex network body ECU).
for LHD:
for RHD:
Measure the voltage and pulse according to the value(s) in the table below.
| Terminal No. (Symbol) | Wiring Color | Terminal Description | Condition | Specified Condition |
|---|---|---|---|---|
| 3B-54 (DIM) - Body ground | LG - Body ground | DIMMER relay drive output | Headlight dimmer switch in high or high flash position | Below 1 V |
| Headlight dimmer switch not in high or high flash position | 11 to 14 V | |||
| G78-5 (HU) - Body ground | Y - Body ground | Headlight dimmer switch high signal input | Headlight dimmer switch in high position | Below 1 V |
| Headlight dimmer switch in low position | Pulse generation*1 11 to 14 V*2 |
|||
| G78-20 (CLTB) - G78-22 (CLTE) | W - V | Automatic light control sensor power supply output | Ignition switch off | Below 1 V |
| Ignition switch ON Headlight dimmer switch in AUTO position |
11 to 14 V | |||
| G78-21 (CLTS) - Body ground | G - Body ground | Automatic light control sensor signal input | Ignition switch off | Below 1 V |
| Ignition switch ON Headlight dimmer switch in AUTO position Automatic light control sensor covered with a hand → Automatic light control sensor exposed to ambient light |
Pulse generation (See waveform 1) | |||
| G78-28 (A) - Body ground | G - Body ground | Headlight dimmer switch AUTO position signal input | Headlight dimmer switch in AUTO position | Below 1 V |
| Headlight dimmer switch not in AUTO position | Pulse generation*1 11 to 14 V*2 |
*1: Main Body ECU (multiplex network body ECU) with 3 Connectors
*2: Main Body ECU (multiplex network body ECU) with 1 Connector
Waveform 1
| Item | Content |
|---|---|
| Terminal No. (Symbol) | G78-21 (CLTS) - Body ground |
| Tool setting | 5 V/DIV., 5 ms./DIV. |
| Condition | Ignition switch ON Headlight dimmer switch in AUTO position Automatic light control sensor covered with a hand → Automatic light control sensor exposed to ambient light |
Tech Tips
If the ambient light becomes brighter, width A becomes narrower.
CHECK FORWARD RECOGNITION CAMERA
Check the forward recognition camera.