CLEARANCE WARNING ECU ASSEMBLY
Disconnect the F52 clearance warning ECU assembly connector.
Measure the voltage and resistance according to value(s) in the table below.
| Terminal No. (Symbol) | Wiring Color | Terminal Description | Condition | Specified Condition |
|---|---|---|---|---|
| F52-15 (IG) - F52-17 (E) | W - W-B | IG power source signal | Engine switch off | Below 1 V |
| Engine switch on (IG) | 11 to 14 V | |||
| F52-17 (E) - Body ground | W-B - Body ground | Ground | Always | Below 1 Ω |
Reconnect the F52 clearance warning ECU assembly connector.
Measure the voltage, resistance and check for pulses according to value(s) in the table below.
| Terminal No. (Symbol) | Wiring Color | Terminal Description | Condition | Specified Condition |
|---|---|---|---|---|
| F52-7 (BOR) - F52-17 (E) | B - W-B | Power source for rear sensor circuit | Engine switch off | Below 1 V |
| Engine switch on (IG), LEXUS parking assist-sensor system on | 7.2 to 8.8 V | |||
| F52-9 (SOF) - F52-17 (E) | SB - W-B | Front sensor communication signal (Front clearance sonar sensor) | Engine switch on (IG), LEXUS parking assist-sensor system on, shift lever in R | Pulse generation (See waveform 2) |
| F52-10 (BBZ) - F52-17 (E) | W - W-B | Clearance warning buzzer signal | Engine switch off | Below 1 V |
| Engine switch on (IG), LEXUS parking assist-sensor system on | 11 to 14 V | |||
| F52-11 (EF) - F52-17 (E) | Y - W-B | Ground for clearance warning buzzer | Buzzer sounding | Pulse generation (See waveform 1) |
| F52-18 (E2) - F52-17 (E) | R - W-B | Ground for rear clearance sonar | Always | Below 1 Ω |
| F52-19 (E1) - F52-17 (E) | R - W-B | Ground for rear clearance sonar | Always | Below 1 Ω |
| F52-21 (BOF) - F52-17 (E) | B - W-B | Power source for front sensor circuit | Engine switch off | Below 1 V |
| Engine switch on (IG), LEXUS parking assist-sensor system on | 7.2 to 8.8 V | |||
| F52-24 (SOR) - F52-17 (E) | G - W-B | Rear sensor communication signal (Rear clearance sonar sensor) | Engine switch on (IG), LEXUS parking assist-sensor system on, shift lever in R | Pulse generation (See waveform 2) |
Using an oscilloscope, check waveform 1.
Waveform 1 (Reference)
| Item | Content |
|---|---|
| Terminal No. (Symbol) | F52-11 (EF) - F52-17 (E) |
| Tool Setting | 2 V/DIV., 500 μsec./DIV. |
| Vehicle Condition | When sonar detects obstacle (buzzer sounds) |
Using an oscilloscope, check waveform 2.
Waveform 2 (Reference)
| Item | Content |
|---|---|
| Terminal No. (Symbol) |
|
| Tool Setting | 5 V/DIV., 1 msec./DIV. |
| Condition | Engine switch on (IG), LEXUS parking assist-sensor system on, shift lever in R |