For a complete wiring diagram Refer to Section 8W.
The Tire Pressure Monitoring System (TPMS) will warn the driver of a low tire pressure based on the vehicle recommended cold placard pressure. The tire pressure will vary with temperature by about 1 psi (6.9 kPa) for every 12 degrees F (6.5 degrees C). This means that when the outside temperature decreases, the tire pressure will decrease. Tire pressure should always be set based on cold inflation tire pressure. This is defined as the tire pressure after a vehicle has not been driven for more than 3 hours - and in outside ambient temperature. . The tire pressure will also increase as the vehicle is driven - this is normal and there should be no adjustment for this increased pressure. The TPM System will warn the driver of a low tire pressure if the tire pressure falls below the low pressure warning threshold for any reason, including low temperature effects. The TPM System will continue to warn the driver of low tire pressure as long as the condition exists, and will not turn off until the tire pressure is at or above recommended cold placard pressure. Once the low tire pressure warning has been illuminated, the tire pressure must be increased to the recommended cold placard pressure in order for the TPM warning lamp to be turned off. The system will automatically update and the TPM warning lamp will extinguish once the updated tire pressures have been received. The vehicle may need to be driven for up to 10 minutes above 15 mph (25 kph) to receive this information. Seasonal temperature changes will affect tire pressure, and the TPM system will monitor the actual tire pressure in the tire. For example, your vehicle may have a recommended cold (parked for more than 3 hours) placard of 30 (207 kPa). If the ambient temperature is 68 degrees F (20 degrees C) and the measured tire pressure is 27 psi (186 kPa), a temperature drop to 20 degrees F (-7 degrees C) will decrease the tire pressure to approximately 23 psi (157 kPa). This tire pressure is sufficiently low enough to turn ON the TPM lamp. Driving the vehicle may cause the tire pressure to rise to approximately 27 psi (186 kPa), but the TPM lamp will still be ON. In this situation, the TPM lamp will turn OFF only after the tires have been inflated to the vehicle’s recommended cold placard pressure value.
Continuously.
A low pressure condition will exist when the tire pressure falls below or is equal to the low pressure threshold value as specified for the vehicle.
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Possible Causes
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INTERMITTENT PERFORMANCE DTC |
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INCORRECT PLACARD VALUES |
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INCORRECT TIRE PRESSURE |
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TIRE PRESSURE SENSOR |
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WCM (SKREEM) |
NOTE: If the incorrect Placard Values were programmed into the WCM/SKREEM, a DTC could be set. Before continuing with any TPM diagnostic test, using the scan tool, check that the correct Placard Values have been programmed in to the module.
NOTE:
If the following conditions are present:
– Low Tire Pressure DTC (C0077) (Active)
– Spare Tire is not equipped with a Tire Pressure Sensor
– Spare Tire is currently on the vehicle
Repair the tire and place it back on the vehicle.
Test drive the vehicle.
If the DTC(s) reset continue with the diagnostic procedure.
NOTE: Before continuing, ensure the tire is free from any leaks or damage that would cause a low tire pressure condition. If a problem is found, repair as necessary and retest.