DESCRIPTION
The tire pressure warning ECU receives an engine speed signal from the ECM. This DTC is stored upon entering signal check mode (test mode), and cleared when an engine speed signal of 1000 rpm is detected for 3 seconds or more. This DTC is output only in signal check mode.
DTC No. |
DTC Detection Condition |
Trouble Area |
---|---|---|
C2194/94 |
Test mode procedure is performed |
|
WIRING DIAGRAM
CAUTION / NOTICE / HINT
NOTICE:
PROCEDURE
1. |
READ VALUE USING TECHSTREAM (ENGINE SPEED) |
(a) Turn the ignition switch off.
(b) Connect the Techstream to the DLC3.
(c) Turn the ignition switch to ON.
(d) Turn the Techstream on.
(e) Enter the following menus: Chassis / Tire Pressure Monitor / Data List.
(f) Check that the values indicated on the Techstream and on the combination meter are the same.
Tire Pressure Monitor
Tester Display |
Measurement Item/Range |
Normal Condition |
Diagnostic Note |
---|---|---|---|
Engine Speed |
Engine speed/ min.: 0 rpm max.: 65535 rpm |
Almost same as actual engine speed |
Speed indicated on combination meter |
OK:
Engine speed indicated on the Techstream and on the combination meter are the same.
OK | ![]() |
USE SIMULATION METHOD TO CHECK |
|
2. |
INSPECT TIRE PRESSURE WARNING ECU (TACH SIGNAL) |
(a) Disconnect the D31 ECU connector. |
|
(b) Start the engine.
(c) Check the waveform of the ECU connector using an oscilloscope while idling the engine.
OK:
Tester Connection |
Condition |
Specified Condition |
---|---|---|
D31-4 (TACH) - D31-9 (GND) |
Idling |
Correct waveform appears as shown |
*1 |
Rear view of wire harness connector (to Tire Pressure Warning ECU) |
Item |
Contents |
---|---|
Tool Setting |
5 V/DIV., 10 ms/DIV. |
HINT:
The wavelength becomes shorter as the engine speed increases.
OK | ![]() |
REPLACE TIRE PRESSURE WARNING ECU |
|
3. |
CHECK HARNESS AND CONNECTOR (TIRE PRESSURE WARNING ECU - ECM) |
(a) Disconnect the D31 ECU connector. |
|
(b) Disconnect the A41 or A49 ECM connector.
(c) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
Tester Connection |
Condition |
Specified Condition |
---|---|---|
D31-4 (TACH) - A41-15 (TACH) |
Always |
Below 1 Ω |
D31-4 (TACH) - A49-26 (TACH) |
Always |
Below 1 Ω |
D31-4 (TACH) - Body ground |
Always |
10 kΩ or higher |
*1 |
Front view of wire harness connector (to Tire Pressure Warning ECU) |
*2 |
Front view of wire harness connector (to ECM) |
*3 |
2GR-FE |
*4 |
1AR-FE |
Result |
Proceed to |
---|---|
OK (for 2GR-FE) |
A |
OK (for 1AR-FE) |
B |
NG |
C |
A | ![]() |
REPLACE ECM (for 2GR-FE) |
B | ![]() |
REPLACE ECM (for 1AR-FE) |
C | ![]() |
REPAIR OR REPLACE HARNESS OR CONNECTOR |
System Diagram
SYSTEM DIAGRAM
Communication Table
Transmitting ECU (Transmitter)
Receiving ECU (Receiver)
Signal
Line
Main body ECU
(Driver side junction block assembly)
Power Back Door ECU
(P ...
On-vehicle Inspection
ON-VEHICLE INSPECTION
CAUTION / NOTICE / HINT
HINT:
Use the same procedure for the RH side and LH side.
The procedure listed below is for the LH side.
PROCEDURE
1. REMOVE FRONT WHEEL
2. SEPARATE FRONT DISC BRAKE CALIPER ASSEMBLY
3. ...
Diagnostic Trouble Code Chart
DIAGNOSTIC TROUBLE CODE CHART
Navigation System
DTC Code
Detection Item
See page
B1532
LVDS Signal Malfunction (from Extension Module)
B1551
HD Radio Tuner ...