C2185

TIRE AND WHEEL: TIRE PRESSURE WARNING SYSTEM: C2121/21-C2125/25,C2181/81-C2185/85: No Signal from Transmitter ID1
C2185/85 - Transmitter ID5 not Received (Test Mode DTC)

DESCRIPTION

The tire pressure warning valve and transmitters that are installed in the tire and wheel assemblies measure the air pressure of the tires. The measured values are transmitted to the tire pressure warning antenna and receiver on the body as radio waves and then sent to the tire pressure warning ECU. The ECU compares the measured air pressure values with the air pressure threshold. When the measured air pressure value is less than this threshold, the warning light in the combination meter comes on.

The tire pressure warning valve and transmitters constantly send radio waves to the tire pressure warning antenna and receiver.

Under the conditions below, the tire pressure warning antenna and receiver is unable to receive the signals from the tire pressure warning valve and transmitters, and a DTC is stored.

* Facilities or devices that use similar radio frequencies are located in the vicinity of the vehicle.

* Devices using similar radio frequencies are used in the vehicle.

* The ID of the tire pressure warning valve and transmitter is mistyped during registration.

* A tire/wheel/transmitter from a different vehicle is installed.

HINT
When no transmitter ID is received from a tire pressure warning valve and transmitter for a total of 20 minutes while the vehicle speed is more than 8 km/h (5 mph) or no transmitter ID is received from the all the tire pressure warning valve and transmitters for a total of 20 minutes, DTCs are stored.

DTCs from C2121/21 to C2125/25 can only be cleared by using the Techstream. DTCs from C2181/81 to C2185/85 can be cleared when the transmitter in the tire pressure warning valve and transmitter sends a forced transmission signal or test mode ends. DTCs from C2181/81 to C2185/85 are output only in test mode.

NOTICE:
When DTCs C2121/21 to C2125/25 are stored in the tire pressure warning ECU, DTC C2173/73 may be stored simultaneously. In such cases, troubleshoot C2173/73 first, then troubleshoot DTCs C2121/21 to C2125/25.

HINT
It is necessary to perform the procedure to identify the tire pressure warning valve and transmitter that is malfunctioning because it cannot be identified by the output DTC.

WIRING DIAGRAM

INSPECTION PROCEDURE

NOTICE:
It is necessary to register the transmitter IDs after replacing the tire pressure warning valve and transmitter and/or the tire pressure warning ECU Programming and Relearning.

PROCEDURE

1. CHECK DTC (C2173/73)

(a) Turn the ignition switch off.

(b) Connect the Techstream to the DLC3.

(c) Turn the ignition switch ON.

(d) Turn the Techstream on.

(e) Read the DTCs. Enter the following menus: Chassis / Tire Pressure Monitor / Trouble Codes.

OK:

DTC C2173/73 is not output.

NOTICE:
When DTC C2173/73 is output, troubleshoot that DTC first. Then troubleshoot DTCs C2121/21 to C2125/25.

NG -- GO TO DTC C2173/73 C2173
OK -- Continue to next step.

2. CHECK FREQUENCY RECEIVING CONDITION

(a) Check that the vehicle is not located in an area described below:

(1) Facilities or devices that use similar radio frequencies are located in the vicinity of the vehicle.

HINT
If the vehicle is located in an area described above, the tire pressure warning light may come on only in a particular area.

(2) Devices using similar radio frequencies are used in the vehicle.

OK:

Facilities, or devices that use similar radio frequencies are not located in the vicinity of the vehicle.

HINT
Radio frequencies may be interrupted due to surroundings or devices installed by the user.

NG -- CHECK IF ANY DEVICE IS INSTALLED BY USER
OK -- Continue to next step.

3. IDENTIFY TRANSMITTER CORRESPONDING TO DTC

(a) Set the tire pressure of all the wheels to the specified value Service Precautions.

(b) Turn the ignition switch off.

(c) Connect the Techstream to the DLC3.

(d) Turn the ignition switch ON.

(e) Turn the Techstream on.

(f) Check the values by referring to the table below. Enter the following menus: Chassis / Tire Pressure Monitor / Data List.

Tire Pressure Monitor:

HINT
*1: It may take about 2 or 3 minutes until the values are displayed.

(g) Rapidly reduce the tire pressure for each wheel at least 40 kPa (0.4 kg/cm2, 5.8 psi) within 30 seconds.

(h) Check the Data List.

NOTICE:
* It takes about 2 or 3 minutes to display the updated tire pressure data.
* If "ID Tire Inflation Pressure" data has not changed, reset the tire pressure to the appropriate specified value and rotate the tire 90 to 270 degrees. Then rapidly reduce the tire pressure and recheck it.
* Record the transmitter ID of which "ID Tire Inflation Pressure" data corresponds to each tire.

(i) After confirming that one of "ID Tire Inflation Pressure" data for one tire (ID1 to ID5) has changed, repeat this procedure one by one. Identify the transmitter that corresponds to the DTC.

Result:

C -- INSPECT TIRE PRESSURE WARNING VALVE AND TRANSMITTER

B -- END
A -- Continue to next step.

4. CHECK HARNESS AND CONNECTOR (ECU - RECEIVER)

(a) Disconnect the E56 ECU connector.

(b) Disconnect the L26 receiver connector.

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

Standard resistance:

NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- Continue to next step.

5. INSPECT TIRE PRESSURE WARNING VALVE AND TRANSMITTER

(a) Turn the ignition switch off.

(b) Connect the Techstream to the DLC3.

(c) Turn the ignition switch ON.

(d) Turn the Techstream on.

(e) Check the values by referring to the table below. Enter the following menus: Chassis / Tire Pressure Monitor / Data List.

Tire Pressure Monitor:

HINT
*1: Displayed only when the ID No. is not registered.

(f) Check the ID number on the identified transmitter by removing it from the tire and wheel.

(g) Confirm that the ID number on the transmitter and recorded transmitter ID match.

Result:

B -- REGISTRATION OF TRANSMITTER ID
A -- Continue to next step.

6. REPLACE TIRE PRESSURE WARNING VALVE AND TRANSMITTER

(a) Replace the tire pressure warning valve and transmitter Removal.

NEXT -- Continue to next step.

7. REGISTRATION OF TRANSMITTER ID

(a) Perform the registration Programming and Relearning.

NEXT -- Continue to next step.

8. READ VALUE USING TECHSTREAM (TIRE INFLATION PRESSURE)

(a) Turn the ignition switch off.

(b) Connect the Techstream to the DLC3.

(c) Turn the ignition switch ON.

(d) Turn the Techstream on.

(e) Check the values by referring to the table below. Enter the following menus: Chassis / Tire Pressure Monitor / Data List.

Tire Pressure Monitor:

HINT
* *1: It may take about 2 or 3 minutes until the values are displayed
* If "ID Tire Inflation Pressure" data has not changed, reset the tire pressure to the appropriate specified value and rotate the tire 90 to 270 degrees. Then rapidly reduce the tire pressure and recheck it.

Result:

B -- END
A -- Continue to next step.

9. REPLACE TIRE PRESSURE WARNING ANTENNA AND RECEIVER

(a) Replace the tire pressure warning antenna and receiver Removal.

NEXT -- Continue to next step.

10. READ VALUE USING TECHSTREAM (TIRE INFLATION PRESSURE)

(a) Set the tire pressure of all the wheels to the specified value Service Precautions.

(b) Turn the ignition switch off.

(c) Connect the Techstream to the DLC3.

(d) Turn the ignition switch ON.

(e) Turn the Techstream on.

(f) Check the values by referring to the table below. Enter the following menus: Chassis / Tire Pressure Monitor / Data List.

Tire Pressure Monitor:

B -- REPLACE TIRE PRESSURE WARNING ECU Removal

A -- END