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For 1990-2009 cars only

DTC C0750, C0755, C0760, or C0765 w/o WC2 or WC8

Circuit Description

The tire pressure monitor (TPM) system has a radio frequency transmitting pressure sensor in each wheel/tire assembly. As vehicle speed increases above 32 km/h (20 mph) the sensors internal roll switch closes which puts the sensors into drive mode. The sensors begin to transmit once every 60 seconds to the remote control door lock receiver (RCDLR) . The data within the sensors radio frequency transmission is translated by the RCDLR into sensor presence, sensor mode, and tire pressure. The RCDLR waits for the first sensor to go into drive mode then checks if all sensors have gone into drive mode.

DTC Descriptors

This diagnostic procedure supports the following DTCs:

    • DTC C0750 Left Front Low Tire Pressure Sensor
    • DTC C0755 Right Front Low Tire Pressure Sensor
    • DTC C0760 Left Rear Low Tire Pressure Sensor
    • DTC C0765 Right Rear Low Tire Pressure Sensor

Condition for Running the DTC

Vehicle speed is above 32 km/h (20 mph).

Conditions for Setting the DTC

Any given sensor does not go into drive mode, or does not transmit at all for 35 minutes.

Action Taken When the DTC Sets

    • A DTC is stored in memory.
    • The driver information center (DIC) displays the SERVICE TIRE MONITOR warning message.
    • The DIC will display the suspect tire pressure as dashes.

Conditions for Clearing the DTC

    • A current DTC will clear when the malfunction is no longer present.
    • A history DTC will clear after 100 consecutive malfunction-free ignition cycles.

Diagnostic Aids

    • When using the J 41760 to activate a sensor, ensure the J-46079 is within 10 feet of the sensor being activated.
    • The sensor activation procedure may have to be repeated up to 3 times before determining a sensor is not transmitting.
    • If the vehicle is stationary for more than 15 minutes after being driven the sensors will go into stationary mode. Always test drive the vehicle over 32 km/h (20 mph) to insure the sensors are in drive mode before viewing tire pressures on the DIC.
    • If there is an open in the class 2 serial data circuit to the receiver, the DIC will display dashes for all tire pressures and the SERVICE TIRE MONITOR warning message.
    • Occasionally sensor transmission will not be received by the RCDLR due to vehicle level radio frequency interference.
    • Loss of, or low vehicle battery voltage, or disconnecting the RCDLR will cause the sensors ID codes to be erased from the RCDLR's memory and set all 4 of the sensor DTCs. If this condition is suspected, refer to Tire Pressure Sensor Learn .
    • Occasionally sensors can become mislocated due to previous tire rotations where the sensor learn procedure was not performed. Always learn the sensors first then test drive to ensure the DTC set is for that actual corner of the vehicle. Refer to Tire Pressure Sensor Learn .

Test Description

The numbers below refer to the step numbers on the diagnostic table.

  1. Tests if the sensors are transmitting after magnetic activation. Since the TPM diagnostic tool can only receive and store sensor transmission data from one sensor at a time, this step must be repeated for each sensor.

  2. Tests if the RCDLR can receive simulated sensor transmissions but not necessarily its ability to translate pressure data. Since the RCDLR compensates for barometric pressure, the tire pressures displayed on the TPM diagnostic tool and the tire pressures displayed on the scan tool may differ as much as +/- 4 psi.

  3. This step tests if the sensors internal roll switch is functioning properly.

Step

Action

Values

Yes

No

Schematic Reference: Tire Pressure Monitoring System Schematics

1

Did you perform the Diagnostic System Check - Vehicle?

--

Go to Step 2

Go to Diagnostic System Check - Vehicle in Vehicle DTC Information

2

Using the J-46079 TPM diagnostic tool in Scan mode, activate each tire pressure sensor using the J 41760 sensor activating magnet and record each sensor's transmission data on the repair order.

Does the TPM diagnostic tool display each sensor's transmission data as specified?

8 digit ID number, accurate tire pressure +/- 2 psi, Learn Mode, good signal strength

Go to Step 3

Go to Step 6

3

  1. Turn ON the ignition, with the engine OFF.
  2. Enable the sensor learn mode by simultaneously pressing the keyless entry transmitter's lock and unlock buttons until a horn chirp sounds.
  3. Using the TPM diagnostic tool in simulate mode, learn 4 simulated sensor IDs into the RCDLR's memory.
  4. With the scan tool, observe all 4-tire pressures.

Does the scan tool display all 4-tire pressures as specified?

LF-10 psi, RF- 20 psi, RR-30 psi, LR-40 psi +/- 4psi

Go to Step 4

Go to Step 7

4

Learn the tire pressure sensors. Refer to Tire Pressure Sensor Learn .

Did you complete the procedure?

--

Go to Step 5

--

5

  1. Use the scan tool in order to clear the DTCs.
  2. Operate the vehicle within the Conditions for Running and Setting the DTC.

Does the DTC reset?

--

Go to Step 6

System OK

6

Replace the suspect tire pressure sensor. Refer to Tire Pressure Indicator Sensor Replacement .

Did you complete the replacement?

--

Go to Step 8

--

7

Replace the remote control door lock receiver (RCDLR). Refer to Remote Control Door Lock Receiver Replacement in Keyless Entry.

Did you complete the replacement?

--

Go to Step 8

--

8

  1. Clear the DTCs with the scan tool.
  2. Operate the vehicle within the Conditions for Running and Setting the DTC.

Does the DTC reset?

--

Go to Step 2

System OK

DTC C0750, C0755, C0760, or C0765 w/ WC2 or WC8

Circuit Description

The tire pressure monitor (TPM) system has a radio frequency transmitting pressure sensor secured to the run flat ring inside each wheel/tire assembly. As vehicle speed increases to above 32 km/h (20 mph), the sensors internal roll switch closes which puts the sensors into drive mode. In this mode the sensors begin to transmit once every 60 seconds to the remote control door lock receiver (RCDLR). The data within the sensors radio frequency transmission is translated by the RCDLR into sensor presence, sensor mode, and tire pressure. The RCDLR waits for the first sensor to go into drive mode, then checks if all sensors have gone into drive mode.

DTC Descriptors

This diagnostic procedure supports the following DTCs:

    • DTC C0750 Left Front Low Tire Pressure Sensor
    • DTC C0755 Right Front Low Tire Pressure Sensor
    • DTC C0760 Left Rear Low Tire Pressure Sensor
    • DTC C0765 Right Rear Low Tire Pressure Sensor

Conditions for Running the DTC

Vehicle speed is at least 40 km/h (20 mph).

Conditions for Setting the DTC

Any given sensor does not go into drive mode, or does not transmit at all for 35 minutes.

Action Taken When the DTC Sets

    • A DTC is stored in memory.
    • The driver information center (DIC) displays the SERVICE TIRE MONITOR warring message.
    • The DIC displays the suspect tire pressure as dashes.

Conditions for Clearing the DTC

    • A current DTC will clear when the malfunction is no longer present.
    • A history DTC will clear after 100 consecutive malfunction-free ignition cycles.

Diagnostic Aids

    • Loss of, or low system battery voltage, or disconnecting the RCDLR will cause the sensor Id codes to be erased from the RCDLRs memory and set all 4 sensor DTCs. If this conditions is suspected, refer to Tire Pressure Sensor Learn .
    • Occasionally sensors can become mislocated due to previous tire rotations where sensor identification (ID) relocation procedure was not performed. Always enter the sensor ID codes in their proper location as noted on the outside of the vehicles wheel mounting flanges to ensure the DTC set is for that actual physical corner of the vehicle. Refer to Tire Pressure Sensor Learn .
    • Occasionally sensor transmissions are not received by the RCDLR due to vehicle level radio frequency interference.

Test Description

The numbers below refer to the step numbers on the diagnostic table.

  1. This step tests if the sensors internal battery level is low

  2. This step tests if the malfunction was system, or vehicle condition related. Some occurrences of this DTC are caused by certain vehicle conditions.

  3. This step tests if the malfunction was corrected by sensor replacement or if the malfunction still exists in the RCDLR.

Step

Action

Yes

No

Schematic Reference: Tire Pressure Monitoring System Schematics

1

Did you perform the Diagnostic System Check - Vehicle?

Go to Step 2

Go to Diagnostic System Check - Vehicle in Vehicle DTC Information

2

  1. Turn ON the ignition, with the engine OFF.
  2. Observe the suspect Pressure Sensor Battery Status Data parameter in Data Displays with a scan tool.

Does the scan tool display the suspect Pressure Sensor Battery Status as Low?

Go to Step 5

Go to Step 3

3

Review the tire pressure monitoring (TPM) system with the customer to verify the conditions under which the DTC set.

Did vehicle conditions cause this DTC to set?

Go to Diagnostic Aids

Go to Step 4

4

  1. Enter the suspect tire pressure sensors ID number into the remote control door lock receivers (RCDLR)s memory. Refer to Tire Pressure Sensor Learn .
  2. Operate the vehicle within the Conditions for Running and Setting the DTC.

Does the DTC reset?

Go to Step 5

System OK

5

  1. Replace the suspect tire pressure sensor. Refer to Tire Pressure Indicator Sensor Replacement .
  2. Operate the vehicle within the Conditions for Setting the DTC.

Does the DTC reset?

Go to Step 6

Go to Step 7

6

Replace the RCDLR. Refer to Remote Control Door Lock Receiver Replacement in Keyless Entry.

Did you complete the replacement?

Go to Step 7

--

7

  1. Clear the DTCs with the scan tool.
  2. Operate the vehicle within the Conditions for Running and Setting the DTC.

Does the DTC reset?

Go to Step 2

System OK