DTC C0750, C0755, C0760, or C0765
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DTC C0750, C0755, C0760, or C0765
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DTC C0750 03
Left Front Tire Pressure Sensor Low Voltage
DTC C0750 29
Left Front Tire Pressure Sensor Too Few Pulses
DTC C0750 39
Left Front Tire Pressure Sensor Internal Malfunction
DTC C0755 03
Right Front Tire Pressure Sensor Low Voltage
DTC C0755 29
Right Front Tire Pressure Sensor Too Few Pulses
DTC C0755 39
Right Front Tire Pressure Sensor Internal Malfunction
DTC C0760 03
Left Rear Tire Pressure Sensor Low Voltage
DTC C0760 29
Left Rear Tire Pressure Sensor Too Few Pulses
DTC C0760 39
Left Rear Tire Pressure Sensor Internal Malfunction
DTC C0765 03
Right Rear Tire Pressure Sensor Low Voltage
DTC C0765 29
Right Rear Tire Pressure Sensor Too Few Pulses
DTC C0765 39
Right Rear Tire Pressure Sensor Internal Malfunction
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Circuit/System Description
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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 body control module (BCM) 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 BCM waits for the first sensor to go into Rolling mode, then checks if all sensors have gone into Rolling mode. If one or more sensors do not go into these modes, or do not transmit at all, the BCM will set DTC C0750, C0755, C0760, or C0765 respectively.
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Conditions for Running the DTC
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The vehicle speed is greater than 40 km/h (25 mph).
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Conditions for Setting the DTC
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A sensor does not transmit for 18 minutes.
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A sensor low battery condition.
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Action Taken When the DTC Sets
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The tire pressure monitor indicator icon on the instrument panel cluster (IPC) will flash for 1 minute and then remain illuminated after the ignition switch is cycled ON and the IPC bulb check is complete.
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If equipped, the driver information center (DIC) displays the suspect tire pressure as dashes.
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If equipped, the DIC displays a service tire monitor type message.
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Conditions for Clearing the DTC
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A current DTC will clear when the malfunction is no longer present and 1 ignition cycle occurs.
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The BCM automatically clears the history DTC when a current DTC is not detected in 100 consecutive drive cycles.
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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.
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Aftermarket wheel valve stem locations can cause a sensor to not function correctly.
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A sensor may have been damaged due to a previous wheel/tire service or flat tire event.
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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
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Occasionally sensor transmissions are not received by the BCM 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.
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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 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.
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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 Indicator Sensor Learn
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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 BCM 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
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Description and Operation
Tire Pressure Monitor Description and Operation
Electrical Information Reference
Scan Tool Reference
Control Module References
for scan tool information
Special Tools
EL-46079/J-46079 Tire Pressure Monitor Diagnostic Tool
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Circuit/System Verification
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1.
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Using the EL-46079/J-46079 , activate each tire pressure sensor and record each sensors transmission data and physical location. Verify EL-46079/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.
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If any of the parameters listed above are not displayed, replace the suspect tire pressure sensor.
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3.
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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.
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5.
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Enable the TPM learn mode. Use the EL-46079/J-46079 in simulate mode to learn 4 simulated sensor transmissions into the BCM. Verify that all 4 simulated sensor locations, IDs, and tire pressures displayed on the TPM special tool match the corresponding scan tool parameters displayed.
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6.
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If the scan tool does not match, replace the K9 BCM.
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7.
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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.
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If the Pressure Sensor Mode does not change, replace the suspect tire pressure sensor.
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Perform the
Diagnostic Repair Verification
after completing the diagnostic procedure.
