TERMINALS OF ECU
CHECK TIRE PRESSURE WARNING ECU AND RECEIVER
(a) Disconnect the M23 tire pressure warning ECU and receiver connector and measure the voltage or resistance on the wire harness side.
|
*a |
Front view of wire harness connector (to Tire Pressure Warning ECU and Receiver) |
|
Terminal No. (Symbol) |
Wiring Color |
Terminal Description |
Condition |
Specified Condition |
|---|---|---|---|---|
|
M23-1 (IG) - M23-12 (GND) |
SB - W-B |
IG power source |
Ignition switch to ON |
10 to 16 V |
|
M23-7 (+B) - M23-12 (GND) |
R - W-B (*1) B - W-B (*2) |
Power supply (from battery) |
Always |
10 to 16 V |
|
M23-12 (GND) - Body ground |
W-B - Body ground |
Ground |
Always |
Below 1 Ω |
(b) Connect the M23 tire pressure warning ECU and receiver connector.
(c) Measure the voltage and resistance according to the value(s) in the table below. If the result is not as specified, the ECU may be malfunctioning.
HINT:
Measure the values on the wire harness side while the connector is connected.
|
*a |
Component with harness connected (Tire Pressure Warning ECU and Receiver) |
- |
- |
|
Terminal No. (Symbol) |
Wiring Color |
Terminal Description |
Condition |
Specified Condition |
|---|---|---|---|---|
|
M23-3 (CLSW) - M23-12 (GND) |
Y - W-B |
Tire pressure warning reset switch |
|
Below 1.5 V |
|
8 to 15 V |
|||
|
M23-4 (RDA) - M23-12 (GND) |
G - W-B |
Output signals |
Ignition switch to ON |
Pulse generation (see waveform 1) |
|
M23-5 (PRG) - M23-12 (GND) |
W - W-B |
Input signals |
Ignition switch to ON |
Pulse generation (see waveform 1) |
(d) Using an oscilloscope, check waveform 1.
|
*a |
Example |
|
*b |
GND |
|
Item |
Contents |
|---|---|
|
Terminal |
M23-4 (RDA) - M23-12 (GND) M23-5 (PRG) - M23-12 (GND) |
|
Tool setting |
5 V/DIV, 5 ms./DIV. |
|
Vehicle condition |
Ignition switch to ON |
HINT:
The waveform shown in the illustration is an example. If the tester displays a waveform that alternates between high and low, where high is a voltage that is between the IG power source voltage and a voltage 2.2 V lower than the IG power source voltage, and where low is a voltage of between 0 and 1.2 V, the ECU can be judged normal.
Problem Symptoms Table
Diagnosis SystemToyota CH-R Service Manual > Solar Sensor: Components
COMPONENTS
ILLUSTRATION
*1
AUTOMATIC LIGHT CONTROL SENSOR
*2
DEFROSTER NOZZLE ASSEMBLY
...
Toyota CH-R Service Manual > Meter / Gauge System: Speed Signal Circuit
DESCRIPTION
The combination meter assembly receives the vehicle speed signal from this circuit.
The wheel speed sensors produce an output that varies according to the vehicle speed.
The wheel speed sensor output is received by the skid control ECU (brake actuator
assembly) which uses this inf ...