CHECK INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY AND MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU)
Remove the main body ECU (multiplex network body ECU) from the instrument panel junction block assembly.
| *1 | Main Body ECU (Multiplex Network Body ECU) | - | - |
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 |
|---|---|---|---|---|
| MB-32 (IG) - Body ground | - | Ignition power supply | Power switch off | Below 1 V |
| Power switch on (IG) | 11 to 14 V | |||
| MB-31 (BECU) - Body ground | - | Auxiliary battery power supply | Power switch off | 11 to 14 V |
| MB-30 (ACC) - Body ground | - | ACC power supply | Power switch off | Below 1 V |
| Power switch on (ACC) | 11 to 14 V | |||
| MB-11 (GND1) - Body ground | - | Ground | Always | Below 1 Ω |
Install the main body ECU (multiplex network body ECU).
Measure the voltage and check the waveform between each connector terminal using an oscilloscope according to the value(s) in the table below.
| Terminal No. (Symbol) | Wiring Color | Terminal Description | Condition | Specified Condition |
|---|---|---|---|---|
| G6-20 (CLTS) - Body ground | SB - Body ground | Automatic light control sensor signal input | Power switch off | Below 1 V |
| Power switch on (IG), headlight dimmer switch in AUTO position, material which blocks light used to cover and then uncover top of automatic light control sensor | Communication waveform generation (See waveform 1) |
|||
| G6-24 (HU) - Body ground | W - Body ground | Headlight dimmer switch high signal input |
|
11 to 14 V |
| Headlight dimmer switch in high position | Below 1 V | |||
| G6-13 (CANL) - Body ground | W - Body ground | CAN communication line | Power switch on (IG) | Pulse generation |
| G6-14 (CANH) - Body ground | BR - Body ground | CAN communication line | Power switch on (IG) | Pulse generation |
| G5-23 (AHBI) - Body ground | BE - Body ground | Auto high beam switch signal input | Combination switch assembly (automatic high beam main switch) on | Below 1 V |
| Combination switch assembly (automatic high beam main switch) off | 11 to 14 V |
*: Low beams do not illuminate in daytime mode. It is necessary to cover the top of the automatic light control sensor with a material which blocks light to activate nighttime mode.
Waveform 1
| Item | Content |
|---|---|
| Terminal No. (Symbol) | G6-20 (CLTS) - Body ground |
| Tool setting | 2 V/DIV., 10 ms./DIV. |
| Condition | Power switch on (IG), headlight dimmer switch in AUTO position, material which blocks light used to cover and then uncover top of automatic light control sensor |
Tech Tips
The communication waveform changes according to the surrounding brightness.
CHECK LANE DEPARTURE WARNING CAMERA