The TMPS fault light comes on periodically. When it does comes on it is usually about 20-30 minutes after driving the car. Often the sensor fault light does not come on at all. This has been a problem that the vehicle has had since 20,000 miles and dates back to 2010. The vehicle was taken to the dealership several times under warranty and the extended warranty and never diagnosed or repaired (they said could not replicate the problem). The TPMS sensors have all been changed twice and the problem still randomly exists. The sensors were originally checked and found to be good. Then they were changed for a generic type of sensor (valve stem style) and still had the same problem. They have subsequently been changed back to new FoMoCo original style sensors with new bands. Could the problem be, tied to incorrect temperature input (I believe the system uses temperature and pressure)? Alternatively, could there be a problem with the harness? Could it be firmware?
My car has 106000 miles.
My car has an automatic transmission.
Yes, firmware, the BCM (body control module), temperature outputs, the harness, faulty batteries, could all be potential causes of this sort of intermittent fault. The problem you having is probably not common though because I do not see a pattern of complaints or any relevant Ford-issued Technical Service Bulletins at NHTSA. As with other complex electrical systems, your best bet is going to be to use the diagnostic decision tree published in the factory service manual and just go through all the possibilities. That is exactly what a responding certified mechanic would do were you to request a diagnostic. In addition, there is a specialized TPMS scanner that mechanics use to get a better view of actual system operation. Using the scan tool during an instance of the malfunction may pinpoint the cause. If you desire that this problem be diagnosed by a certified Mechanic, dispatched by YourMechanic right to your location, please request a TPMS warning light diagnostic and the responding certified mechanic will get this resolved for you. If you have further questions or concerns, do not hesitate to re-contact YourMechanic as we are always here to help you.
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