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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 (RF) transmitting pressure sensor inside each wheel/tire assembly. As vehicle speed increases, centrifugal force closes the sensors internal roll switch, which puts the sensors into drive mode. The remote control door lock receiver (RCDLR) receives and translates the data within each sensor's RF transmission into sensor presents, sensor mode and tire pressure. Once vehicle speed is 32 km/h (20 mph), or greater, the RCDLR waits for the first sensor to go into drive mode then checks if all sensors have gone into drive mode.

Condition for Running the DTC

Vehicle speed is 32 km/h (20 mph), or greater.

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 DIC displays the SERVICE TIRE MONITOR warning 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 50 consecutive malfunction free ignition cycles.
    • Using a scan tool.

Diagnostic Aids

    • The sensor activation/scan procedure using the J-46079 TPM diagnostic tool with the J 41760 sensor activating tool, may have to be repeated up to 3 times before determining a sensor is malfunctioning.
    • 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 .
    • 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 sensor transmission will not be received by the RCDLR due to vehicle level RF interference.

Test Description

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

  1. Tests if the sensors will transmit valid data with good signal strength in response to a magnetic activation. During this step it is important to observe the signal strength graph on the TPM tool's display screen when the sensor transmits. Any more than 1/4 graph displayed can be considered good signal strength. The TPM diagnostic tool can only store transmission data from 1 sensor at a time, therefore the scan button must be pressed and released prior to each sensor activation.

  2. Tests if the RCDLR can receive and translate data from simulated sensor transmissions

  3. 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 Tire Pressure Monitor Diagnostic System Check?

 

Go to Step 2

Go to Diagnostic System Check - Tire Pressure Monitoring

2

  1. Using the J-46079 TPM tool, press and release the scan button.
  2. Using the J 41760 sensor activating tool, activate each tire pressure sensor and record each sensor's transmission data on the repair order.

Does the TPM 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. Enable the TPM learn mode. Refer to Tire Pressure Sensor Learn .
  2. Using the TPM tool in simulate mode, learn 4 simulated sensor transmissions into the RCDLR's memory.
  3. With the scan tool observe all 4 tire pressures.

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

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

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

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 sensor. Refer to Tire Pressure Indicator Sensor Replacement .

Did you complete the replacement?

 

Go to Step 8

-

7

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

Did you complete the replacement?

 

Go to Step 8

-

8

  1. Use the scan tool in order to clear the DTC.
  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 (RF) 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 RF 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.

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 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.
    • Using a scan tool

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 Id relocation procedure was not performed. Always enter the sensor Id codes in there 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 RF interference.

Test Description

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

  1. Tests if the sensors internal battery level is low

  2. Tests if the malfunction was system, or vehicle condition related

  3. 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 Tire Pressure Monitor Diagnostic System Check?

Go to Step 2

Go to Diagnostic System Check - Tire Pressure Monitoring

2

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

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

Go to Step 5

Go to Step 3

3

Since some occurrences of this DTC are caused by certain vehicle conditions. Review the 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 RCDLRs 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. 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 2

System OK