CHECK INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY AND MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU)
| *1 | Main Body ECU (Multiplex Network Body ECU) | - | - |
Disconnect the instrument panel junction block assembly and main body ECU (multiplex network body ECU) connectors.
Measure the voltage 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 |
|---|---|---|---|---|
| 4F-1 - Body ground | B - Body ground | Battery power supply | Always | 11 to 14 V |
| 4E-1 - Body ground | B - Body ground | Battery power supply | Always | 11 to 14 V |
If the result is not as specified, there may be a malfunction in the wire harness.
Measure the 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 |
|---|---|---|---|---|
| 4B-7 - Body ground | W-B - Body ground | Ground | Always | Below 1 Ω |
If the result is not as specified, there may be a malfunction in the wire harness.
Reconnect 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 |
|---|---|---|---|---|
| 4D-28 - Body ground | V - Body ground | Taillight drive output | Light control switch in tail or head position | 11 to 14 V |
| Light control switch off | Below 1 V | |||
| 4C-29 - Body ground | R - Body ground | H-LP LH relay drive output | Light control switch in tail or head position | Below 1 V |
| Light control switch off | 11 to 14 V | |||
| 4D-12 - Body ground*3 | BE - Body ground | Rear fog light drive output | Light control switch in tail or head position, fog light switch in rear position | 11 to 14 V |
| Light control switch in tail or head position, fog light switch off | Below 1 V | |||
| O2-1 (DIM) - Body ground | V - Body ground |
|
Light control switch in tail or head position | Below 1 V |
| Light control switch off | 11 to 14 V | |||
| 4C-15 - Body ground | GR - Body ground | Parking brake switch input | Parking brake switch on | Below 1 V |
| Parking brake switch off | 11 to 14 V | |||
| O2-24 (HU) - Body ground | V - Body ground | Dimmer switch high position signal input | Dimmer switch in high position | Below 1 V |
| Dimmer switch not in high position | Pulse generation | |||
| O2-10 (HF) - Body ground | L - 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 | Pulse generation | |||
| O2-19 (CLTB) - O2-21 (CLTE) | GR - W | Automatic light control sensor power supply output | Engine switch off | Below 1 V |
| Engine switch on (IG), light control switch in AUTO position | 11 to 14 V | |||
| O-20 (CLTS) - Body ground | R - Body ground | Automatic light control sensor signal input | Engine switch off | Below 1 V |
| Automatic light control system operating | Communication waveform generation (See waveform 1) |
|||
| O2-23 (RFOG) - Body ground*3 | P - Body ground | Fog light switch rear position input | Fog light switch in rear position | Below 1 V |
| Fog light switch off | Pulse generation | |||
| O2-8 (A) - Body ground | P - Body ground | Light control switch AUTO position signal input | Light control switch in AUTO position | Below 1 V |
| Light control switch not in AUTO position | Pulse generation | |||
| O2-12 (HEAD) - Body ground | Y - Body ground | Light control switch head position input | Light control switch in head position | Below 1 V |
| Light control switch not in head position | Pulse generation | |||
| O2-22 (TAIL) - Body ground | B - Body ground | Light control switch tail position signal input | Light control switch in tail or head position | Below 1 V |
| Light control switch not in tail or head position | Pulse generation | |||
| O1-4 (MILE) - Body ground | LG - Body ground | Outside handle foot lights drive output | Outside handle foot light illuminate | 11 to 14 V |
| Outside handle foot light off | Below 3 V |
*1: for LHD
*2: for RHD
*3: w/ Rear Fog Light
If the result is not as specified, the main body ECU (multiplex network body ECU) or instrument panel junction block assembly may be malfunctioning.
Waveform 1
| Item | Content |
|---|---|
| Tool setting | 2 V/DIV., 10 ms./DIV. |
Tech Tips
The communication waveform changes according to the surrounding brightness.
CHECK HEADLIGHT LIGHT CONTROL ECU SUB-ASSEMBLY LH
Disconnect the A3 headlight light control ECU sub-assembly LH connector.
Measure the resistance and voltage 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 |
|---|---|---|---|---|
| A3-4 (IG) - Body ground | B - Body ground | Ignition power supply | Engine switch off | Below 1 V |
| Engine switch on (IG) | 11 to 14 V | |||
| A3-13 (ECUB) - Body ground | W - Body ground | Battery power supply | Light control switch off | Below 1 V |
| Light control switch in tail or head position | 11 to 14 V | |||
| A3-12 (GND) - Body ground | W-B - Body ground | Ground | Always | Below 1 Ω |
Reconnect the A3 headlight light control ECU sub-assembly LH connector.
Tech Tips
Since the headlight light control ECU sub-assembly LH uses a waterproof connector, the voltage and pulses cannot be checked directly. The values listed are for reference only.
Measure the voltage and check of pulses according to the value(s) in the table below.
| Terminal No. (Symbol) | Wiring Color | Terminal Description | Condition | Specified Condition |
|---|---|---|---|---|
| A3-8 (RLD2) - Body ground | G - Body ground | Daytime running light/clearance light drive output | Daytime running light or clearance light on | Below 1 V |
| Daytime running light and clearance light off | Pulse generation | |||
| A3-11 (TNS) - Body ground | G - Body ground | LH turn signal light signal input | Engine switch on (IG), LH turn signal light off | Below 1 V |
| Engine switch on (IG), LH turn signal light blinking | 11 to 14 V ←→ Below 1 V | |||
| A3-16 (SBR) - A3-15 (SGR) | GR - LG | Rear height control sensor power supply | Engine switch on (IG) | 4.75 to 5.25 V |
| A3-17 (SHRL) - A3-15 (SGR) | G - LG | Rear height control sensor signal input | Engine switch on (IG), vehicle unloaded, vehicle stopped | Approximately 2.5 V (value decreases as the front of the vehicle is raised) |
| A3-20 (LINL) - Body ground | LG - Body ground | LIN communication | Engine switch on (IG) | Pulse generation |
CHECK HEADLIGHT LIGHT CONTROL ECU SUB-ASSEMBLY RH
Disconnect the A11 headlight light control ECU sub-assembly RH connector.
Measure the resistance and voltage 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 |
|---|---|---|---|---|
| A11-4 (IG) - Body ground | B - Body ground | Ignition power supply | Engine switch off | Below 1 V |
| Engine switch on (IG) | 11 to 14 V | |||
| A11-13 (ECUB) - Body ground | B - Body ground | Battery power supply | Light control switch off | Below 1 V |
| Light control switch in tail or head position | 11 to 14 V | |||
| A11-12 (GND) - Body ground | W-B - Body ground | Ground | Always | Below 1 Ω |
Reconnect the A11 headlight light control ECU sub-assembly RH connector.
Tech Tips
Since the headlight light control ECU sub-assembly RH uses a waterproof connector, the voltage and pulses cannot be checked directly. The values listed are for reference only.
Measure the voltage and check of pulses according to the value(s) in the table below.
| Terminal No. (Symbol) | Wiring Color | Terminal Description | Condition | Specified Condition |
|---|---|---|---|---|
| A11-8 (RLD2) - Body ground | G - Body ground | Daytime running light/clearance light drive output | Daytime running light or clearance light on | Below 1 V |
| Daytime running light and clearance light off | Pulse generation | |||
| A11-11 (TNS) - Body ground | G - Body ground | RH turn signal light signal input | Engine switch on (IG), RH turn signal light off | Below 1 V |
| Engine switch on (IG), RH turn signal light blinking | 11 to 14 V ←→ Below 1 V | |||
| A11-20 (LINL) - Body ground | LG - Body ground | LIN communication | Engine switch on (IG) | Pulse generation |
CHECK COMBINATION METER ASSEMBLY
Measure the voltage according to the value(s) in the table below.
| Terminal No. (Symbol) | Wiring Color | Terminal Description | Condition | Specified Condition |
|---|---|---|---|---|
| O4-4 (ER) - Body ground | P - Body ground | Turn signal switch right signal input | Turn signal switch in neutral position | 11 to 14 V |
| Turn signal switch in right turn position | Below 1 V | |||
| O4-5 (EL) - Body ground | GR - Body ground | Turn signal switch left signal input | Turn signal switch in neutral position | 11 to 14 V |
| Turn signal switch in left turn position | Below 1 V | |||
| O4-11 (HZSW) - Body ground | W - Body ground | Hazard warning signal switch signal (Input) | Engine switch on (IG), hazard warning signal switch not pressed | 11 to 14 V |
| Engine switch on (IG), hazard warning signal switch pressed | Below 1 V | |||
| O4-12 (HAZM) - Body ground | B - Body ground | Hazard warning signal switch signal (Output) | Engine switch on (IG), hazard warning signal switch not pressed | 11 to 14 V |
| Engine switch on (IG), hazard warning signal switch pressed | Below 1 V |