TERMINALS OF ECU
1. CLEARANCE WARNING ECU ASSEMBLY
(a) Disconnect the D79 clearance warning ECU assembly connector.
(b) Measure the voltage and resistance according to the value(s) in the table below.
Terminal No. (Symbol) |
Wiring Color |
Terminal Description |
Condition |
Specified Condition |
---|---|---|---|---|
D79-9 (CLSW) - D79-30 (E) |
B - W |
Back sonar or clearance sonar switch assembly power source signal |
Engine switch on (IG), clearance sonar main switch on |
11 to 14 V |
D79-9 (CLSW) - D79-30 (E) |
B - W |
Back sonar or clearance sonar switch assembly power source signal |
Engine switch on (IG), clearance sonar main switch off |
Below 1 V |
D79-1 (IG) - D79-30 (E) |
GR - W |
IG power source signal |
Engine switch off |
Below 1 V |
Engine switch on (IG) |
11 to 14 V |
|||
D79-30 (E) - Body ground |
W - Body ground |
Ground |
Always |
Below 1 Ω |
(c) Reconnect the D79 clearance warning ECU assembly connector.
(d) 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 |
---|---|---|---|---|
D79-22 (BOR) - D79-30 (E) |
V - W |
Power source for rear sensor circuit |
Engine switch off |
Below 1 V |
Engine switch on (IG), clearance sonar main switch on |
7.2 to 8.8 V |
|||
D79-8 (SOF) - D79-30 (E) |
LG - W |
Front sensor communication signal (Front clearance sonar sensor) |
Engine switch on (IG), clearance sonar main switch on, shift lever in R |
Pulse generation (See waveform 2) |
D79-13 (ER) - D79-30 (E) |
Y - W |
Clearance warning buzzer signal |
Buzzer sounding |
Pulse generation (See waveform 1) |
D79-23 (E1) - D79-30 (E) |
L - W |
Ground for rear clearance sonar |
Always |
Below 1 V |
D79-6 (E5) - D79-30 (E) |
BR - W |
Ground for front clearance sonar |
Always |
Below 1 V |
D79-4 (BOF) - D79-30 (E) |
W - W |
Power source for front sensor circuit |
Engine switch off |
Below 1 V |
Engine switch on (IG), clearance sonar main switch on |
7.2 to 8.8 V |
|||
D79-24 (SOR) - D79-30 (E) |
Y - W |
Rear sensor communication signal (Rear clearance sonar sensor) |
Engine switch on (IG), clearance sonar main switch on, shift lever in R |
Pulse generation (See waveform 2) |
(e) Using an oscilloscope, check waveform 1.
(1) Waveform 1 (Reference)
Item |
Content |
---|---|
Terminal No. (Symbol) |
D79-13 (ER) - D79-30 (E) |
Tool Setting |
2 V/DIV., 500 μsec./DIV. |
Vehicle Condition |
When sonar detects obstacle (buzzer sounds) |
Buzzer volume |
Buzzer sounding |
HINT:
The amplitude of the waveform changes according to the set volume.
(f) Using an oscilloscope, check waveform 2.
(1) Waveform 2 (Reference)
Item |
Content |
---|---|
Terminal No. (Symbol) |
|
Tool Setting |
5 V/DIV., 1 msec./DIV. |
Condition |
Engine switch on (IG), clearance sonar main switch on, shift lever in R |
HINT:
The waveforms for CH1 and CH2 are same.
Seat Belt Buckle Switch LH Circuit Malfunction (B1656/38)
DESCRIPTION
The seat belt buckle switch LH circuit consists of the center airbag sensor assembly
and front seat inner belt assembly LH.
DTC B1656/38 is stored when a malfunction is detected in the seat belt buckle
switch LH circuit.
DTC No.
...
Starting the engine
Shift the shift lever to “P” and
apply the brakes.
Touch the Toyota emblem side of the electronic key to the “ENGINE START STOP”
switch.
An alarm will sound to indicate that the start function cannot detect the electronic
key that is touched ...
Components
COMPONENTS
ILLUSTRATION
ILLUSTRATION
ILLUSTRATION
ILLUSTRATION
ILLUSTRATION
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