TERMINALS OF ECU
1. CHECK TIRE PRESSURE WARNING ECU AND RECEIVER
(a) Disconnect the T14 tire pressure warning ECU and receiver connector and measure the voltage and resistance on the wire harness side.
*A |
w/o Wireless Door Lock System |
*B |
w/o Smart Key System with Wireless Door Lock System |
*C |
w/ Smart Key System |
*a |
Front view of wire harness connector (to Tire Pressure Warning ECU and Receiver) |
Terminal No. (Symbol) |
Wiring Color |
Terminal Description |
Condition |
Specified Condition |
---|---|---|---|---|
T14-1 (IG) - T14-12 (GND) |
LG - W-B |
IG power source |
Ignition switch ON |
10 to 16 V |
T14-12 (GND) - Body ground |
W-B - Body ground |
Ground |
Always |
Below 1 Ω |
Terminal No. (Symbol) |
Wiring Color |
Terminal Description |
Condition |
Specified Condition |
---|---|---|---|---|
T25-1 (IG) - T25-12 (GND) |
LG - W-B |
IG power source |
Ignition switch ON |
10 to 16 V |
T25-7 (+B) - T25-12 (GND |
BE - W-B |
Power supply (from battery) |
Always |
10 to 16 V |
T25-12 (GND) - Body ground |
W-B - Body ground |
Ground |
Always |
Below 1 Ω |
Terminal No. (Symbol) |
Wiring Color |
Terminal Description |
Condition |
Specified Condition |
---|---|---|---|---|
T24-1 (IG) - T24-12 (GND) |
LG - W-B |
IG power source |
Ignition switch ON |
10 to 16 V |
T24-7 (+B) - T24-12 (GND) |
BE - W-B |
Power supply (from battery) |
Always |
10 to 16 V |
T24-12 (GND) - Body ground*1 |
W-B - Body ground |
Ground |
Always |
Below 1 Ω |
(b) Connect the T14*1, T25*2, T24*3 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.
Terminal No. (Symbol) |
Wiring Color |
Terminal Description |
Condition |
Specified Condition |
---|---|---|---|---|
T14-3 (CLSW) - T14-12 (GND)*1 T25-3 (CLSW) - T25-12 (GND)*2 T24-3 (CLSW) - T24-12 (GND)*3 |
R - W-B |
Tire pressure warning reset switch |
|
Below 1.5 V |
|
8 to 15 V |
|||
T14-4 (RDA) - T14-12 (GND)*1 T25-4 (RDA) - T25-12 (GND)*2 T24-4 (RDA) - T24-12 (GND)*3 |
B - W-B |
Output signals |
Ignition switch ON |
Pulse generation (see waveform 1) |
T14-5 (PRG) - T14-12 (GND)*1 T25-5 (PRG) - T25-12 (GND)*2 T24-5 (PRG) - T24-12 (GND)*3 |
GR - W-B |
Input signals |
Ignition switch ON |
Pulse generation (see waveform 1) |
(d) Using an oscilloscope, check waveform 1.
Waveform 1:
Item |
Contents |
---|---|
Terminal |
T14-4 (RDA) - T14-12 (GND)*1 T25-4 (RDA) - T25-12 (GND)*2 T24-4 (RDA) - T24-12 (GND)*3 T14-5 (PRG) - T14-12 (GND)*1 T25-5 (PRG) - T25-12 (GND)*2 T24-5 (PRG) - T24-12 (GND)*3 |
Tool setting |
5 V/DIV., 5 ms./DIV. |
Vehicle condition |
Ignition switch ON |
*a |
Example |
*b |
GND |
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.
Parts Location
PARTS LOCATION
ILLUSTRATION
*A
for Hydraulic Brake Booster
*B
for Vacuum Brake Booster
*C
for Automatic Transmission
*D
for Manual Transmission
*1
SKID CONTROL ECU (BRAKE ACT ...
How To Proceed With Troubleshooting
CAUTION / NOTICE / HINT
HINT:
Use these procedures to troubleshoot the key reminder warning system.
*: Use the Techstream.
PROCEDURE
1.
VEHICLE BROUGHT TO WORKSHOP
NEXT
...
Gauges and meters
The following gauges, meters and displays illuminate when the engine switch is
in the ON position.
Tachometer
Displays the engine speed in revolutions per minute.
Speedometer
Displays the vehicle speed.
Engine coolant temperature gauge
Displays the engine coolant temperature.
Fuel gauge
...