DTC C0750, C0755, C0760, or C0765 With UH3
Diagnostic Instructions
| • | Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. |
| • | Review Strategy Based Diagnosis for an overview of the diagnostic approach. |
| • | Diagnostic Procedure Instructions provides an overview of each diagnostic category. |
DTC Descriptors
DTC C0750: Left Front Low Tire Pressure SensorDTC C0755: Right Front Low Tire Pressure Sensor
DTC C0760: Left Rear Low Tire Pressure Sensor
DTC C0765: Right Rear Low Tire Pressure Sensor
Diagnostic Fault Information
Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance |
|---|---|---|---|---|
Left Front Tire Pressure Receiver Voltage Reference | C0750 | C0750 | C0750 | -- |
Right Front Tire Pressure Receiver Voltage Reference | C0755 | C0755 | C0755 | -- |
Left Rear Tire Pressure Receiver Voltage Reference | C0760 | C0760 | C0760 | -- |
Right Rear Tire Pressure Receiver Voltage Reference | C0765 | C0765 | C0765 | -- |
Left Front Tire Pressure Receiver Low Reference | -- | C0750 | -- | -- |
Right Front Tire Pressure Receiver Low Reference | -- | C0755 | -- | -- |
Left Rear Tire Pressure Receiver Low Reference | -- | C0760 | -- | -- |
Right Rear Tire Pressure Receiver Low Reference | -- | C0765 | -- | -- |
Left Front Tire Pressure Receiver Signal | C0750 | C0750 | C0750 | -- |
Right Front Tire Pressure Receiver Signal | C0755 | C0755 | C0755 | -- |
Left Rear Tire Pressure Receiver Signal | C0760 | C0760 | C0760 | -- |
Right Rear Tire Pressure Receiver Signal | C0765 | C0765 | C0765 | -- |
Circuit/System Description
The tire pressure monitor (TPM) system has a radio frequency (RF) transmitting pressure sensor in each wheel/tire assembly. As vehicle speed increases, centrifugal force closes the sensor internal roll switch, which puts the sensor into rolling mode. The sensor signals are received by the tire pressure receivers mounted near each wheel. Each receiver has a 5-volt reference circuit, a low reference circuit, and signal circuit connected to the tire pressure module. The tire pressure module transmits the individual sensor signals to the remote control door lock receiver (RCDLR) which translates the data contained in the tire pressure sensor RF transmissions into sensor presence, sensor mode, and tire pressure. Once vehicle speed is 40 km/h (25 mph) or greater, the RCDLR waits for the sensors to go into rolling mode. If one or more sensors do not go into rolling mode, or do not transmit at all, the RCDLR will set DTC C0750, C0755, C0760, or C0765 respectively.
Conditions for Running the DTC
Vehicle speed is 40 km/h (25 mph)or greater for 2 minutes.
Conditions for Setting the DTC
| • | A sensor does not transmit for 18 minutes. |
| • | A malfunctioning tire pressure receiver. |
| • | An open/high resistance, short to voltage, or short to ground in the tire pressure module power or ground circuit. |
| • | An open, short to voltage, short to ground, or high resistance in a tire pressure receiver 5-volt reference, low reference, or signal circuit. |
Action Taken When the DTC Sets
| • | The tire pressure monitor indicator icon on the instrument panel cluster (IPC) flashes for 1 minute and then remains illuminated after the ignition switch is cycled ON and the IPC bulb check is complete. |
| • | The driver information center (DIC) displays the suspect tire pressure as dashes. |
| • | The DIC displays a service tire monitor type message. |
Conditions for Clearing the DTC
| • | A current DTC will clear when the malfunction is no longer present and 1 ignition cycle occurs. |
| • | The RCDLR automatically clears the history DTC when a current DTC is not detected in 100 consecutive drive cycles. |
Diagnostic Aids
| • | Some aftermarket wheel valve stem holes are located further from the wheel rim than original equipment wheels. When using the TPM special tool to activate a sensor, ensure the tool antenna is no further than 15 cm (6 in) from the sensor and is aiming upward. |
| • | Aftermarket wheel valve stem locations can cause a sensor to not function correctly. |
| • | A sensor may have been damaged due to a previous wheel/tire service or flat tire event. |
| • | The use of other than GM approved tire sealants can obstruct the sensor pressure sensing port and cause inaccurate tire pressure readings. If this condition is verified, remove the sealer from the tire and replace the sensor. Refer to Tire Pressure Indicator Sensor Replacement. |
| • | Occasionally sensor transmissions are not received by the RCDLR due to vehicle level RF interference from items such as but not limited to aftermarket ignition systems, DVD players, CB radios, or metallic type window tinting. |
| • | The sensor activation procedure may have to be repeated up to 3 times before determining a sensor is malfunctioning. In the event a particular sensor's information is displayed on the special tool upon activation but the horn does not chirp, it may be necessary to rotate the wheel valve stem to a different position due to the RF signal is being blocked by another component. |
| • | Occasionally sensors can become mislocated due to previous tire rotations where the sensor learn procedure was not performed or stray sensor transmissions have been received from other vehicles. Always learn the sensors to ensure the DTC set is for that actual physical corner of the vehicle. Refer to Tire Pressure Sensor Learn. |
| • | A sensor low battery condition will set a sensor DTC but will not illuminate the low tire pressure indicator or display a message on the DIC, if equipped. The sensor battery condition can be verified in the scan tool RCDLR data list. If a sensor low battery condition is indicated on the scan tool, the sensor will need to be replaced. Refer to Tire Pressure Indicator Sensor Replacement. |
Reference Information
Schematic Reference
Tire Pressure Monitoring System Schematics
Connector End View Reference
Description and Operation
Tire Pressure Monitor Description and Operation
Electrical Information Reference
Scan Tool Reference
Control Module References for Scan Tool Information
Special Tools
J-46079 Tire Pressure Monitor Diagnostic Tool
Circuit/System Testing
- Ignition OFF, test for less than 2.0 ohms of resistance between the tire pressure module ground circuit terminal 10 and ground.
- Ignition ON, verify that a test lamp illuminates between the tire pressure module terminal 1 and ground.
- Ignition OFF, disconnect the harness connector at the affected tire pressure receiver.
- Ignition OFF, test for less than 2 ohms of resistance between the low reference circuit terminal 3 and ground.
- Ignition ON, test for 4.75-5.25 volts between the 5-volt reference circuit terminal 1 and ground.
- Ignition OFF, replace the affected tire pressure receiver with a known good part from one of the other locations.
- Ignition ON, use the special tool to simulate the tire pressure sensor. Verify the scan tool displays an accurate tire pressure that matches 27.6 kPa (4 psi) of the special tool simulation display parameters.
- Using the J-46079 , activate each tire pressure sensor and record each sensors transmission data and physical location. Verify the J-46079 displays an 8-digit ID number, accurate tire pressure 27.6 kPa (4 psi), Learn Mode, and at least a 1/4 graph signal strength displayed.
- Verify that the tire pressure sensors ID and locations displayed on the scan tool match the ID and location recorded from the special tool.
- Test drive the vehicle above 40 km/h (25 mph) for greater than 2 minutes. With the scan tool, observe the suspect Pressure Sensor Mode data parameter. Verify the sensor mode changes to Rolling.
| ⇒ | If greater than the specified range, test the ground circuit for an open/high resistance. |
| ⇒ | If the test lamp does not illuminate, test for an open/high resistance or short to ground in the B+ circuit. If the circuit tests normal, replace the tire pressure module. |
| ⇒ | If greater than the specified range, test the low reference circuit for an open/high resistance. If circuit tests normal, replace the tire pressure module. |
| ⇒ | If less than the specified range, test the 5-volt reference circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the tire pressure module. |
| ⇒ | If greater than the specified range, test the 5-volt reference circuit for a short to voltage. If the circuit tests normal, replace the tire pressure module. |
| ⇒ | If the parameters do not match, test the signal circuit for a short to ground, open/high resistance, or short to voltage. If the circuit tests normal, replace the tire pressure module. |
| ⇒ | If any of the parameters listed above are not displayed, replace the suspect tire pressure sensor. |
| ⇒ | If the ID and location do not match, perform the Tire Pressure Sensor Learn procedure. |
| ⇒ | If the suspect Pressure Sensor Mode does not change, replace the suspect tire pressure sensor. |
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
| • | Control Module References for RCDLR replacement, setup, and programming |
DTC C0750, C0755, C0760, or C0765 Without UH3
Diagnostic Instructions
| • | Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. |
| • | Review Strategy Based Diagnosis for an overview of the diagnostic approach. |
| • | Diagnostic Procedure Instructions provides an overview of each diagnostic category. |
DTC Descriptors
DTC C0750: Left Front Low Tire Pressure SensorDTC C0755: Right Front Low Tire Pressure Sensor
DTC C0760: Left Rear Low Tire Pressure Sensor
DTC C0765: Right Rear Low Tire Pressure Sensor
Circuit/System Description
The tire pressure monitor (TPM) system has a radio frequency (RF) transmitting pressure sensor in each wheel/tire assembly. As vehicle speed increases, centrifugal force closes the sensors internal roll switch, which puts the sensor into Rolling mode. The remote control door lock receiver (RCDLR) receives and translates the data contained in the tire pressure sensor RF transmissions into sensor presence, sensor mode, and tire pressure. Once vehicle speed is greater than 40km/h (25 mph), the RCDLR waits for the sensors to go into rolling mode. If one or more sensors do not go into rolling mode, or do not transmit at all, the RCDLR will set DTC C0750, C0755, C0760, or C0765 respectively.
Conditions for Running the DTC
Vehicle speed is 40 km/h (25 mph) or greater for 2 minutes.
Conditions for Setting the DTC
A sensor does not transmit for 18 minutes.
Action Taken When the DTC Sets
| • | The tire pressure monitor indicator icon on the instrument panel cluster (IPC) flashes for 1 minute and then remains illuminated after the ignition switch is cycled ON and the IPC bulb check is complete. |
| • | The driver information center (DIC) displays the suspect tire pressure as dashes. |
| • | The DIC displays the servive tire monitor type message. |
Conditions for Clearing the DTC
| • | A current DTC will clear when the malfunction is no longer present and 1 ignition key cycle occurs. |
| • | The RCDLR automatically clears the history DTC when a current DTC is not detected in 100 consecutive drive cycles. |
Diagnostic Aids
| • | Some aftermarket wheel valve stem holes are located further from the wheel rim than original equipment wheels. When using the TPM special tool to activate a sensor, ensure the tool antenna is no further than 15 cm (6 in) from the sensor and is aiming upward. |
| • | Aftermarket wheel valve stem locations can cause a sensor to not function correctly. |
| • | A sensor may have been damaged due to a previous wheel/tire service or flat tire event. |
| • | The use of other than GM approved tire sealants can obstruct the sensor pressure sensing port and cause inaccurate tire pressure readings. If this condition is verified, remove the sealer from the tire and replace the sensor. Refer to Tire Pressure Indicator Sensor Replacement. |
| • | Occasionally sensor transmissions are not received by the RCDLR due to vehicle level RF interference from items such as but not limited to aftermarket ignition systems, DVD players, CB radios, or metallic type window tinting. |
| • | The sensor activation procedure may have to be repeated up to 3 times before determining a sensor is malfunctioning. In the event a particular sensor's information is displayed on the special tool upon activation but the horn does not chirp, it may be necessary to rotate the wheel valve stem to a different position due to the RF signal is being blocked by another component. |
| • | Occasionally sensors can become mislocated due to previous tire rotations where the sensor learn procedure was not performed or stray sensor transmissions have been received from other vehicles. Always learn the sensors to ensure the DTC set is for that actual physical corner of the vehicle. Refer to Tire Pressure Sensor Learn. |
| • | A sensor low battery condition will set a sensor DTC but will not illuminate the low tire pressure indicator or display a message on the DIC, if equipped. The sensor battery condition can be verified in the scan tool RCDLR data list. If a sensor low battery condition is indicated on the scan tool, the sensor will need to be replaced. Refer to Tire Pressure Indicator Sensor Replacement. |
Reference Information
Description and Operation
Tire Pressure Monitor Description and Operation
Electrical Information Reference
Scan Tool Reference
Control Module References for Scan Tool Information
Special Tools
J-46079 Tire Pressure Monitor Diagnostic Tool
Circuit/System Verification
- Using the J-46079 , activate each tire pressure sensor and record each sensors transmission data and physical location. Verify J-46079 displays the 8-digit ID number, accurate tire pressure +/- 27.6 kPa (4 psi), Learn Mode, and at least a 1/4 graph signal strength displayed.
- With the scan tool, verify tire pressure sensors ID and locations displayed on the scan tool match the IDs and locations recorded from the special tool.
- Enable the TPM learn mode. Use the J-46079 in simulate mode to learn 4 simulated sensor transmissions into the RCDLR. Verify that all 4 simulated sensor locations, IDs, and tire pressures displayed on the TPM special tool match the corresponding scan tool parameters displayed.
- Test drive the vehicle above 40 km/h (25 mph) for greater than 2 minutes. With the scan tool, observe the suspect Pressure Sensor Mode data parameter. Verify the sensor mode changes to Rolling.
| ⇒ | If any of the parameters listed above are not displayed, replace the suspect tire pressure sensor. |
| ⇒ | If the IDs and locations do not match, perform the Tire Pressure Sensor Learn. |
| ⇒ | If the scan tool does not match, replace the RCDLR. |
| ⇒ | If the Pressure Sensor Mode does not change, replace the suspect tire pressure sensor. |
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
| • | Control Module References for RCDLR replacement, setup, and programming |
