TERMINALS OF ECU
CHECK ECM
HINT:
As a waterproof connector is used for the ECM, voltage, resistance and waveform inspections cannot be performed. The voltage, resistance and waveform values are provided for reference only.
(a) Measure the voltage and resistance according to the value(s) in the table below.
Terminal No. (Symbol) | Wiring Color | Terminal Description | Condition | Specified Condition |
---|---|---|---|---|
A37-27 (STP) - D2-53 (E1) | Y - BR | Stop light switch assembly signal | Brake pedal depressed | 11 to 14 V |
Brake pedal released | Below 1 V | |||
A37-41 (CCS) - D2-53 (E1) | B - BR | Cruise control main switch circuit | Cruise control main switch (ON/OFF button) not pushed | 1 MΩ or higher |
Cruise control main switch (ON/OFF button) pushed | Below 2.5 Ω | |||
+RES switch ON | 235 to 245 Ω | |||
-SET switch ON | 617 to 643 Ω | |||
CANCEL switch ON | 1509 to 1571 Ω | |||
A37-42 (ST1-) - D2-53 (E1) | BR - BR | Stop light switch assembly signal | Engine switch on (IG), brake pedal depressed | Below 1 V |
Engine switch on (IG), brake pedal released | 11 to 14 V |
CHECK FORWARD RECOGNITION CAMERA
NOTICE:
(a) Measure the voltage and resistance according to the value(s) in the table below.
Terminal No. (Symbol) | Wiring Color | Terminal Description | Condition | Specified Condition |
---|---|---|---|---|
U14-3 (LKSW) - U14-10 (GND) | GR - BR | Steering pad switch assembly signal (distance control signal) | Engine switch on (IG), steering pad switch assembly (vehicle-to-vehicle distance control switch) on | Below 1 V |
Engine switch on (IG), steering pad switch assembly (vehicle-to-vehicle distance control switch) off | 4.75 to 5.25 V | |||
U14-7 (IGB) - U14-10 (GND) | SB - BR | Power source | Engine switch on (IG) | 11 to 14 V |
Engine switch off | Below 1 V | |||
U14-8 (BZ) - U14-10 (GND) | W - BR | Skid control buzzer assembly output | Engine switch on (IG), buzzer not sounding | 11 to 14 V |
Engine switch on (IG), buzzer sounding | Below 1 V | |||
U14-10 (GND) - Body ground | BR - Body ground | Ground | Always | Below 1 Ω |
(b) Check for pulses according to the value(s) in the table below.
HINT:
If the waveform is not similar to that shown in the illustration, a malfunction of a CAN bus line, terminating resistor, or the forward recognition camera is suspected.
Terminal No. (Symbol) | Wiring Color | Terminal Description | Condition | Specified Condition |
---|---|---|---|---|
U14-5 (CA1P) - U14-10 (GND) | V - BR | CAN communication signal | Engine switch on (IG) | Pulse generation (See waveform 1) |
U14-6 (CANH) - U14-10 (GND) | B - BR | CAN communication signal | Engine switch on (IG) | Pulse generation (See waveform 1) |
U14-11 (CA1N) - U14-10 (GND) | P - BR | CAN communication signal | Engine switch on (IG) | Pulse generation (See waveform 2) |
U14-12 (CANL) - U14-10 (GND) | W - BR | CAN communication signal | Engine switch on (IG) | Pulse generation (See waveform 2) |
(1) Waveform 1
Item | Content |
---|---|
Tester Connection |
|
Tool Setting | 1 V/DIV., 10 μs./DIV. |
Condition | Engine switch on (IG) |
HINT:
The waveform varies depending on the CAN communication signal.
(2) Waveform 2
Item | Content |
---|---|
Tester Connection |
|
Tool Setting | 1 V/DIV., 10 μs./DIV. |
Condition | Engine switch on (IG) |
HINT:
The waveform varies depending on the CAN communication signal.
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