Dtc C2191/91 Vehicle Speed Signal Error (Test Mode Dtc)

Suspension. Yaris. Ncp93, 131
Tire Pressure Monitoring. Yaris. Ncp93, 131

DESCRIPTION

WIRING DIAGRAM

INSPECTION PROCEDURE

READ VALUE USING TECHSTREAM (VEHICLE SPEED)

INSPECT TIRE PRESSURE WARNING ECU (SPD SIGNAL)

CHECK HARNESS AND CONNECTOR (TIRE PRESSURE WARNING ECU - COMBINATION METER)

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.

DTC No.
DTC Detection Condition
Trouble Area
C2191/91
Vehicle speed signal circuit malfunction
  1. Combination meter
  2. Vehicle speed sensor
  3. Harness or connector
  4. Tire pressure warning ECU

WIRING DIAGRAM


Yaris. Ncp93, 131.Tire Pressure Monitoring.Tire Pressure Warning System (For Sedan). Dtc C2191/91 Vehicle Speed Signal Error (Test Mode Dtc)


INSPECTION PROCEDURE

NOTICE:
  1. When replacing the tire pressure warning ECU, read the transmitter IDs stored in the old ECU using a Techstream and write them down before removal.
  2. It is necessary to perform registration (YARIS_NCP93 RM000000XN107JX.html) of the transmitter IDs into the tire pressure warning ECU after the ECU has been replaced.
1.READ VALUE USING TECHSTREAM (VEHICLE SPEED)

  1. Turn the ignition switch off.

  1. Connect a Techstream to the DLC3.

  1. Turn the ignition switch to ON and the Techstream on.

  1. Enter the following menus: Chassis / Tire Pressure Monitor / Data List

  1. 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
    Vehicle Speed
    		Vehicle speed/
    min.: 0 km/h (0 mph)
    max.: 255 km/h (158 mph)
    		Almost same as actual vehicle speed
    		Speed indicated on combination meter
    OK:
    Vehicle speed indicated on the Techstream and on the combination meter are the same.


NG
Go to step 2
OK

USE SIMULATION METHOD TO CHECK (YARIS_NCP93 RM00000135202EX.html)

2.INSPECT TIRE PRESSURE WARNING ECU (SPD SIGNAL)


    Yaris. Ncp93, 131.Tire Pressure Monitoring.Tire Pressure Warning System (For Sedan). Dtc C2191/91 Vehicle Speed Signal Error (Test Mode Dtc)

  1. Disconnect the D78 ECU connector.

  1. Jack up the vehicle.

  1. Move the shift lever to N.

  1. Turn the ignition switch to ON.

  1. Check the waveform of the ECU connector using an oscilloscope, while turning the wheel slowly.

    OK:
    Tester Connection
    		Switch Condition
    		Specified Condition
    D78-2 (SPD) - D78-9 (GND)
    		Ignition switch ON
    		Correct waveform is as shown
    Tool Setting
    Item
    		Contents
    Tool Setting
    		2 V/DIV., 20 ms/DIV.
    Vehicle Condition
    		Rotate driving wheel slowly
    HINT:
    1. The wavelength becomes shorter as the vehicle speed increases.
    2. Depending on the vehicle, the output waveform voltage may rise to 12 V if influenced by optionally installed systems.


NG
Go to step 3
OK

REPLACE TIRE PRESSURE WARNING ECU (YARIS_NCP93 RM0000024T801VX.html)

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


    Yaris. Ncp93, 131.Tire Pressure Monitoring.Tire Pressure Warning System (For Sedan). Dtc C2191/91 Vehicle Speed Signal Error (Test Mode Dtc)

  1. Disconnect the D78 ECU connector.

  1. Disconnect the D1 meter connector.

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

    Standard resistance:
    Tester Connection
    		Condition
    		Specified Condition
    D78-2 (SPD) - D1-16 (+S)
    		Always
    		Below 1 Ω
    D78-2 (SPD) - Body ground
    		Always
    		10 kΩ or higher
    Result
    Result
    		Proceed to
    NG
    		A
    OK
    		B


B
REPLACE COMBINATION METER (YARIS_NCP93 RM000000IN001JX.html)
A

REPAIR OR REPLACE HARNESS OR CONNECTOR