CHECK MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU) AND INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY
| *A | Main Body ECU (Multiplex Network Body ECU) with 2 Connectors | - | - |
| *1 | Main Body ECU (Multiplex Network Body ECU) | - | - |
| *a | 2 Connectors | - | - |
| *A | Main Body ECU (Multiplex Network Body ECU) with 3 Connectors | - | - |
| *1 | Main Body ECU (Multiplex Network Body ECU) | - | - |
| *a | 3 Connectors | - | - |
Disconnect the instrument panel junction block assembly and main body ECU (multiplex network body ECU) connectors.
Measure the voltage and resistance on the wire harness side connector according to the value(s) in the table below.
| Terminal No. (Symbol) | Wiring Color | Terminal Description | Condition | Specified Condition |
|---|---|---|---|---|
| 4D-11 - Body ground | LA - Body ground | Ground | Always | Below 1 Ω |
| 4D-23 - Body ground | BE - Body ground | Battery power supply | Always | 11 to 14 V |
| 4K-1 - Body ground | B - Body ground | Battery power supply | Always | 11 to 14 V |
Connect the instrument panel junction block assembly and main body ECU (multiplex network body ECU) connectors.
Measure the voltage and check for pulses according to the value(s) in the table below.
| Terminal No. (Symbol) | Wiring Color | Terminal Description | Condition | Specified Condition |
|---|---|---|---|---|
| 4A-48 - Body ground | B - Body ground | Battery power supply | Always | 11 to 14 V |
| 4F-4 - Body ground | LG - Body ground | Clearance lights drive output | Light control switch in tail or head position | 11 to 14 V |
| Light control switch off | Below 1 V | |||
| 4F-6 - Body ground | B - Body ground | Back-up light drive output | Ignition switch off | Below 1 V |
| Ignition switch ON | 11 to 14 V | |||
| 4F-17 - Body ground | B - Body ground | BACK UP LP relay drive output | Ignition switch off | Below 1 V |
| Ignition switch ON | 11 to 14 V | |||
| 4F-21 - Body ground | GR - Body ground | BACK UP LP relay drive output | Ignition switch off | Below 1 V |
| Ignition switch ACC | 11 to 14 V | |||
| 4F-25 - Body ground | GR - Body ground | Front fog light drive output | Light control switch in tail or head position, fog light switch in front position | Below 1 V |
| Light control switch in tail or head position, fog light switch off | 11 to 14 V | |||
| 4F-26 - Body ground | L - Body ground | Daytime running light system drive output | Daytime running light system operating | Below 1 V |
| Daytime running light system not operating | 11 to 14 V | |||
| 4F-27 - Body ground | R - Body ground | Headlight relay drive output | Light control switch in head position | Below 1 V |
| Light control switch not in head position | 11 to 14 V | |||
| 4F-28 - Body ground | G - Body ground | Parking brake switch input | Ignition switch ON, parking brake switch on | Below 1 V |
| Ignition switch ON, parking brake switch off | 11 to 14 V | |||
| 4H-16 - Body ground | LA-Y - Body ground | Taillights (rear light assembly), license plate lights and rear fog lights* drive output | Light control switch in tail or head position | 11 to 14 V |
| Light control switch off | Below 1 V | |||
| 4H-17 - Body ground | LA-Y - Body ground | Taillights (rear combination light assembly) drive output | Light control switch in tail or head position | 11 to 14 V |
| Light control switch off | Below 1 V | |||
| 4H-26 - Body ground* | LG - Body ground | Rear fog light relay power supply output | Light control switch in tail or head position | 11 to 14 V |
| Light control switch off | Below 1 V | |||
| F18-24 (DIM) - Body ground | BE - Body ground | High beam headlight drive output | Dimmer switch in high or high flash position | Below 1 V |
| Dimmer switch in low position | 11 to 14 V | |||
| F19-8 (A) - Body ground | B - Body ground | Light control switch AUTO position signal input | Light control switch in AUTO position | Below 1 V |
| Ignition switch off, light control switch not in AUTO position | 11 to 14 V or Pulse generation | |||
| F19-10 (HF) - Body ground | SB - Body ground | Dimmer switch high flash position signal input | Dimmer switch in high flash position | Below 1 V |
| Dimmer switch not in high flash position | 11 to 14 V or Pulse generation | |||
| F19-12 (HEAD) - Body ground | W - Body ground | Light control switch head position input | Light control switch in head position | Below 1 V |
| Ignition switch off, light control switch not in head position | 11 to 14 V or Pulse generation | |||
| F19-19 (CLTB) - F19-21 (CLTE) | L - G | Automatic light control sensor power supply output | Ignition switch off | Below 1 V |
| Ignition switch ON | 11 to 14 V | |||
| F19-20 (CLTS) - Body ground | R - Body ground | Automatic light control sensor signal input | Ignition switch off | Below 1 V |
| Ignition switch ON, light control switch in AUTO position | Communication waveform generation (See waveform 1) |
|||
| F19-22 (TAIL) - Body ground | LG - Body ground | Light control switch tail position signal input | Light control switch in tail or head position | Below 1 V |
| Ignition switch off, light control switch not in tail or head position | 11 to 14 V or Pulse generation | |||
| F19-23 (RFOG) - Body ground* | LG - Body ground | Fog light switch rear position input | Fog light switch in rear position | Below 1 V |
| Ignition switch off, fog light switch off | 11 to 14 V or Pulse generation | |||
| F19-24 (HU) - Body ground | Y - Body ground | Dimmer switch high position signal input | Dimmer switch in high position | Below 1 V |
| Dimmer switch not in high position | 11 to 14 V or Pulse generation | |||
| F19-26 (FFOG) - Body ground | GR - Body ground | Fog light switch front position input | Fog light switch in front position | Below 1 V |
| Ignition switch off, fog light switch off | 11 to 14 V or Pulse generation |
*: w/ Rear Fog Light
Waveform 1
| Item | Content |
|---|---|
| Tester Connection | F19-20 (CLTS) - Body ground |
| Tool setting | 2 V/DIV., 10 ms./DIV. |
| Vehicle condition | Ignition switch ON, light control switch in AUTO position |
Tech Tips
The communication waveform changes according to the surrounding brightness.
CHECK COMBINATION METER ASSEMBLY
CHECK OUTER MIRROR CONTROL ECU ASSEMBLY LH (w/ Door Mirror Foot Light)
CHECK OUTER MIRROR CONTROL ECU ASSEMBLY RH (w/ Door Mirror Foot Light)