CHECK HEADLIGHT LEVELING ECU
Disconnect the A67 headlight leveling ECU connector.
Measure the voltage and resistance according to the value(s) in the table below.
| Terminal No. (Symbol) | Wiring Color | Terminal Description | Condition | Specified Condition |
|---|---|---|---|---|
| A67-1 (IG) - Body ground | L - Body ground | Ignition power supply | Ignition switch off | Below 1 V |
| Ignition switch ON | 11 to 14 V | |||
| A67-9 (E1) - Body ground | W-B - Body ground | Ground | Always | Below 1 Ω |
If the result is not as specified, there may be a malfunction on the wire harness side.
Reconnect the A67 headlight leveling ECU connector.
Measure the voltage and resistance according to the value(s) in the table below.
| Terminal No. (Symbol) | Wiring Color | Terminal Description | Condition | Specified Condition |
|---|---|---|---|---|
| A67-3 (HDLP) - A67-9 (E1) | BR - W-B | Low beam headlight signal input | Low beam headlights on | Below 1 V |
| Low beam headlights off | 11 to 14 V | |||
| A67-5 (INIT) - A67-9 (E1) | Y - W-B | Initialization signal input | Terminal LVL and terminal CG of DLC3 connected | Below 1 V |
| Terminal LVL and terminal CG of DLC3 not connected | 4.5 to 5.5 V | |||
| A67-6 (WNG) - A67-9 (E1) | LG - W-B | Warning light drive output | Warning light on | Below 1 V |
| Warning light off | 11 to 14 V | |||
| A67-10 (RH+) - A67-9 (E1) | G - W-B | Leveling motor RH power supply | Ignition switch off | Below 1 V |
| Ignition switch ON | 11 to 14 V | |||
| A67-11 (LH+) - A67-9 (E1) | W - W-B | Leveling motor LH power supply | Ignition switch off | Below 1 V |
| Ignition switch ON | 11 to 14 V | |||
| A67-12 (SBR) - A67-21 (SGR) | R - BR | Rear height control sensor power supply | Ignition switch off | Below 1 V |
| Ignition switch ON | 4.75 to 5.25 V | |||
| A67-16 (SPDR) - A67-9 (E1) | V - W-B | Vehicle speed signal input | Vehicle is driven at approximately 20 km/h (12 mph) | Pulse generation (See waveform 1) |
| A67-17 (RHT) - A67-9 (E1) | Y - W-B | Leveling motor RH operation signal input | With low beam headlights on, vehicle height not changed | Below 1 V |
| With low beam headlights on, vehicle height changed and maintained for more than 3 seconds | 1.0 to 14.4 V | |||
| A67-18 (LHT) - A67-9 (E1) | BR - W-B | Leveling motor LH operation signal input | With low beam headlights on, vehicle height not changed | Below 1 V |
| With low beam headlights on, vehicle height changed and maintained for more than 3 seconds | 1.0 to 14.4 V | |||
| A67-19 (SHRL) - A67-21 (SGR) | Y - BR | Rear height control sensor signal input | Ignition switch off | Below 1 V |
| Ignition switch ON | 0.5 to 4.5 V | |||
| A67-21 (SGR) - A67-9 (E1) | BR - W-B | Rear height control sensor ground | Always | Below 1 Ω |
| A67-23 (RH-) - A67-9 (E1) | W-B - W-B | Leveling motor RH ground | Always | Below 1 Ω |
| A67-24 (LH-) - A67-9 (E1) | W-B - W-B | Leveling motor LH ground | Always | Below 1 Ω |
Waveform 1
| Item | Content |
|---|---|
| Terminal No. (Symbol) | A67-16 (SPDR) - A67-9 (E1) |
| Tool setting | 5 V/DIV., 20 ms./DIV. |
| Condition | Vehicle is driven at approximately 20 km/h (12 mph) |
Tech Tips
When the system is functioning normally, one wheel revolution generates 4 pulses. As the vehicle speed increases, the width indicated by (A) in the illustration narrows.