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.
Problem Symptoms Table
PROBLEM SYMPTOMS TABLE
HINT:
Use the table below to help determine the cause of problem symptoms. If multiple
suspected areas are listed, the potential causes of the symptoms are listed in order
of probability in the "Suspected Area" column of ...
Disassembly
DISASSEMBLY
PROCEDURE
1. REMOVE STEERING RACK BOOT CLIP (for LH Side)
(a) Using pliers, remove the steering rack boot clip.
2. REMOVE STEERING RACK BOOT CLIP (for RH Side)
HINT:
Perform the same procedure as for the LH side.
3. REMOVE NO. 2 STEERING RAC ...
Performance Decline of Brake Function (C1441)
DESCRIPTION
The skid control ECU judges brake failure conditions have occurred based on the
signal from the brake pedal load sensing switch and master cylinder pressure sensor.
NOTICE:
Do not intentionally stop the engine when driving. Even when no malfun ...