TERMINALS OF ECU
CHECK 4WD ECU ASSEMBLY
(a) Measure the voltage and resistance of the connector.
| Terminal No. (Symbol) | Wiring Color | Terminal Description | Condition | Specified Condition |
|---|---|---|---|---|
| R10-10 (4WDS) - R10-4 (GND) | P - W-B | AWD lock mode switch signal | Engine switch on (IG) AWD lock mode switch released → pressed and held | 11 to 14 V → Below 1 V |
| R10-6 (CANH) - R10-5 (CANL) | B - W | HIGH-level CAN bus wire - LOW-level CAN bus wire | Cable disconnected from negative (-) battery terminal | 54 to 69 Ω |
| R10-4 (GND) - Body ground | W-B - Body ground | Ground | Always | Below 1 Ω |
| R10-3 (IG1) - R10-4 (GND) | B - W-B | Power source voltage | Engine switch on (IG) | 11 to 14 V |
| R10-2 (SLC+) - R10-1 (SLC-) | L - B | 4WD linear solenoid signal | Shift lever in D, engine idling | Pulse generation (See waveform 1) |
If the result is not as specified, the 4WD ECU assembly may have a malfunction.
(b) Using an oscilloscope, check the waveform 1.
Waveform 1 (Reference)| Item | Content |
|---|---|
| Terminal No. (Symbol) | R10-2 (SLC+) - R10-1 (SLC-) |
| Tester Range | 2 V/DIV., 1 msec./DIV. |
| Condition | Shift lever in D, engine idling |

Diagnosis System
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