TERMINALS OF ECU
CLEARANCE WARNING ECU ASSEMBLY
(a) Disconnect the J38 clearance warning ECU assembly connector.
(b) 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 |
---|---|---|---|---|
J38-1 (IG) - J38-30 (E) | SB - W-B | IG power source signal | Engine switch off | Below 1 V |
Engine switch on (IG) | 11 to 14 V | |||
J38-30 (E) - Body ground | W-B - Body ground | Ground | Always | Below 1 Ω |
(c) Reconnect the J38 clearance warning ECU assembly connector.
(d) Measure the voltage and resistance and check for pulses according to the value(s) in the table below.
Terminal No. (Symbol) | Wiring Color | Terminal Description | Condition | Specified Condition |
---|---|---|---|---|
J38-4 (BOF) - J38-30 (E) | P - W-B | Power source for front sensor circuit | Engine switch off | Below 1 V |
| 11 to 14 V | |||
J38-6 (E5) - J38-30 (E) | L - W-B | Ground for front clearance sonar | Always | Below 1 Ω |
J38-8 (SOF) - J38-30 (E) | B - W-B | Front sensor communication signal (Front clearance sonar sensor) |
| Pulse generation (Refer to waveform 1) |
J38-14 (CBZ) - J38-13 (EF) | Y - P | No. 1 clearance warning buzzer signal | Buzzer sounding | Pulse generation (Refer to waveform 2) |
J38-15 (BBZ) - J38-16 (ER) | R - W | No. 2 clearance warning buzzer signal | Buzzer sounding | Pulse generation (Refer to waveform 2) |
J38-22 (BOR) - J38-30 (E) | LG - W-B | Power source for rear sensor circuit | Engine switch off | Below 1 V |
| 11 to 14 V | |||
J38-23 (E1) - J38-30 (E) | GR - W-B | Ground for rear clearance sonar | Always | Below 1 Ω |
J38-24 (SOR) - J38-30 (E) | SB - W-B | Rear sensor communication signal (Rear clearance sonar sensor) |
| Pulse generation (Refer to waveform 3) |
(e) Using an oscilloscope, check waveform 1.
(1) Waveform 1 (Reference)
Item | Content |
---|---|
Measurement terminal | J38-8 (SOF) - J38-30 (E) |
Measurement setting | 5 V/DIV., 1 ms./DIV. |
Condition |
|
(f) Using an oscilloscope, check waveform 2.
(1) Waveform 2 (Reference)
Item | Content |
---|---|
Measurement terminal |
|
Measurement setting | 2 V/DIV., 500 μs./DIV. |
Condition | Buzzer sounding |
HINT:
The amplitude of the waveform changes according to the set volume.
(g) Using an oscilloscope, check waveform 3.
(1) Waveform 3 (Reference)
Item | Content |
---|---|
Measurement terminal | J38-24 (SOR) - J38-30 (E) |
Measurement setting | 5 V/DIV., 1 ms./DIV. |
Condition |
|
ECM
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COMBINATION METER ASSEMBLY
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