C2191

TIRE AND WHEEL: TIRE PRESSURE WARNING SYSTEM: C2191/91: Vehicle Speed Signal Error (Test Mode DTC)
C2191/91 - Vehicle Speed Signal Error (Test Mode DTC)

DESCRIPTION

The tire pressure warning ECU receives a vehicle speed signal from the combination meter. This DTC is stored upon entering test mode, and cleared when a vehicle speed signal of 20 km/h (12 mph) is detected for 3 seconds or more. This DTC is output only in test mode.





WIRING DIAGRAM





INSPECTION PROCEDURE

NOTICE:
* When replacing the tire pressure warning ECU, read the transmitter IDs stored in the old ECU using the Techstream and write them down before removal.
* It is necessary to perform initialization Initialization after registration Registration of the transmitter IDs into the tire pressure warning ECU after the ECU has been replaced.

PROCEDURE

1. READ VALUE USING TECHSTREAM (VEHICLE SPEED)

(a) Turn the ignition switch to OFF.

(b) Connect the Techstream to the DLC3.

(c) Turn the ignition switch to ON and the tester on.

(d) Enter the following menus: Chassis / Tire Pressure Monitor / Data List

(e) Check that the values indicated on the tester and on the combination meter are the same.

Tire Pressure Monitor





OK:

Vehicle speed indicated on the tester and on the combination meter are the same.

NG -- INSPECT TIRE PRESSURE WARNING ECU (SPD SIGNAL)

OK -- USE SIMULATION METHOD TO CHECK How To Proceed With Troubleshooting

2. INSPECT TIRE PRESSURE WARNING ECU (SPD SIGNAL)

(a) Disconnect the H18 ECU connector.





(b) Jack up the vehicle.

(c) Shift the lever to the neutral position.

(d) Turn the ignition switch to ON.

(e) Check the waveform of the ECU connector using an oscilloscope, while turning the wheel slowly.

OK:





Tool Setting





HINT
The wavelength becomes shorter as the vehicle speed increases.

NG -- CHECK HARNESS AND CONNECTOR (ECU - COMBINATION METER)

OK -- REPLACE TIRE PRESSURE WARNING ECU Removal

3. CHECK HARNESS AND CONNECTOR (ECU - COMBINATION METER)

(a) Disconnect the H18 ECU connector.





(b) Disconnect the C37 meter connector.

(c) Measure the resistance according to the value(s) in the table below.

Standard resistance:





NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR

OK -- REPLACE COMBINATION METER Removal