PRE-COLLISION SYSTEM TERMINALS OF ECU
CHECK PRE-COLLISION CITY SENSOR
Disconnect the M4 pre-collision city sensor connector.
Note:DTCs may be output when connectors are disconnected during inspection. Therefore, be sure to clear the DTCs using the GTS once the inspection has been completed.
Do not apply excessive force to the M4 pre-collision city sensor connector.
Measure the voltage and resistance according to the value(s) in the table below.
Terminal No. (Symbol)
Wiring Color
Terminal Description
Condition
Specified Condition
M4-9 (PCSW) - Body ground
GR - Body ground
Pre-collision system cancel switch assembly signal
Pre-collision system cancel switch assembly being pressed
Below 1 Ω
Pre-collision system cancel switch assembly not being pressed
100 kΩ or higher
M4-7 (IG1) - Body ground
B - Body ground
Power source
Ignition switch ON
11 to 14 V
Ignition switch off
Below 1 V
M4-10 (GND) - Body ground
W-B - Body ground
Ground
Always
Below 1 Ω
Tip:If the result is not as specified, there may be a malfunction on the wire harness side.
Reconnect the M4 pre-collision city sensor connector.
Measure the voltage according to the value(s) in the table below.
Terminal No. (Symbol)
Wiring Color
Terminal Description
Condition
Specified Condition
M4-8 (BUZ) - Body ground
P - Body ground
Pre-collision city heater operation signal
Ignition switch ON
Pre-collision city heater not operating
11 to 14 V
Ignition switch ON
Pre-collision city heater operating
0 to 1.5 V
M4-1 (SPR) - Body ground
V - Body ground
Pre-collision city heater drive signal
Ignition switch ON
Pre-collision city heater not operating
11 to 14 V
Ignition switch ON
Pre-collision city heater operating
Below 1 V
Check for pulses according to the value(s) in the table below.
Terminal No. (Symbol)
Wiring Color
Terminal Description
Condition
Specified Condition
M4-5 (CA1P) - Body ground
B - Body ground
CAN communication signal
Ignition switch ON
Pulse generation
(See waveform 1)
M4-11 (CA1N) - Body ground
W - Body ground
CAN communication signal
Ignition switch ON
Pulse generation
(See waveform 1)
-
Waveform 1
CAN communication signal
Item
Content
Tester Connection
CH1: M4-5 (CA1P) - Body ground
CH2: M4-11 (CA1N) - Body ground
Tool Setting
1 V/DIV., 50 μsec./DIV.
Condition
Ignition switch ON
Tip:If the result is not as specified, the CAN bus line, terminating resistor circuit (or part with this circuit) or pre-collision city sensor is malfunctioning.