TERMINALS OF ECU
1. CHECK TIRE PRESSURE WARNING ECU
HINT:
Inspect the connectors from the back side while the connectors are connected.
(a) Disconnect the L14 tire pressure warning antenna and receiver connector.
(b) Measure the voltage according to the value(s) in the table below.
Terminal No. (Symbol) |
Wiring Color |
Terminal Description |
Condition |
Specified Condition |
---|---|---|---|---|
D31-12 (RDA) - D31-9 (GND) |
Y - W-B |
Tire pressure warning antenna and receiver signal |
Ignition switch ON |
11 to 14 V |
(c) Connect the L14 tire pressure warning antenna and receiver connector.
(d) Measure the voltage and resistance according to the value(s) in the table below. If the result is not as specified, the ECU may have a malfunction.
Terminal No. (Symbol) |
Wiring Color |
Terminal Description |
Condition |
Specified Condition |
---|---|---|---|---|
D31-2 (SPD) - D31-9 (GND) |
P - W-B |
Vehicle speed signal |
Vehicle driving |
Pulse generation (see waveform 1) |
D31-3 (TC) - D31-9 (GND) |
BR - W-B |
TC terminal |
Terminal TC not connected |
11 to 14 V |
D31-4 (TACH) - D31-9 (GND) |
V - W-B |
Engine speed signal |
Engine running |
Pulse generation (see waveform 2) |
D31-5 (IND) - D31-9 (GND) |
LG - W-B |
Tire pressure warning light output signal |
|
Below 0.5 V |
After ignition switch is turned to ON, tire pressure warning light illuminates for 3 seconds. |
0.9 to 3.2 V |
|||
D31-6 (RF5V) - D31-9 (GND) |
R - W-B |
Tire pressure warning antenna and receiver power source |
Ignition switch ON |
11 to 14 V |
D31-7 (IG) - D31-9 (GND) |
GR - W-B |
IG power source |
Ignition switch ON |
11 to 14 V |
D31-9 (GND) - Body ground |
W-B - Body ground |
Ground |
Always |
Below 1 Ω |
D31-10 (SIL) - D31-9 (GND) |
P - W-B |
Diagnostic communication |
Ignition switch ON |
8 to 14 V |
D31-11 (GND2) - D31-9 (GND) |
W - W-B |
Tire pressure warning antenna and receiver ground |
Always |
Below 1 Ω |
D31-12 (RDA) - D31-9 (GND) |
Y - W-B |
Tire pressure warning antenna and receiver signal |
Ignition switch ON |
11 to 14 V |
(e) Using an oscilloscope, check waveform 1.
Item |
Content |
---|---|
Terminal |
D31-2 (SPD) - D31-9 (GND) |
Tool setting |
5 V/DIV, 20 ms./DIV. |
Vehicle condition |
Driving at approximately 20 km/h (12 mph) |
HINT:
The wavelength becomes shorter as the vehicle speed increases.
(f) Using an oscilloscope, check waveform 2.
Item |
Content |
---|---|
Terminal |
D31-4 (TACH) - D31-9 (GND) |
Tool setting |
5 V/DIV., 10 ms./DIV. |
Vehicle condition |
Idling |
HINT:
The wavelength becomes shorter as the engine speed increases.
Unlock Warning Switch Circuit
DESCRIPTION
The key unlock warning switch assembly turns on when the ignition key is inserted
into the ignition key cylinder and turns off when the ignition key is removed.
The main body ECU (driver side junction block assembly) operates the key confinemen ...
If your vehicle overheats
The following may indicate that your vehicle is overheating.
• The engine coolant temperature gauge reaches the maximum, or a loss of
engine power is experienced. (For example, the vehicle speed does not increase.)
• Steam comes out from under the hood ...
Engine Switch Illumination Circuit
DESCRIPTION
The illuminated entry system controls the engine switch illumination.
WIRING DIAGRAM
PROCEDURE
1.
PERFORM ACTIVE TEST USING TECHSTREAM
(a) Connect the Techstream to the DLC3.
(b) Turn the ignition switch to O ...