Some 2015-2019 Ford and Lincoln vehicles may experience front or rear park aid sensor false alerts with no diagnostic trouble codes (DTCs) present.
False park aid alerts with no DTCs in the park aid system are usually due to snow, slush, fog, salt, ice, frost build-up, car wash, and/or heavy rain.
If no codes are found this is a normal vehicle characteristic. The vehicle owners have the ability, on some vehicles, to turn the park aid system off in certain weather conditions.
1. Park aid sensor
2. Park aid silicon ring
3. Park aid retainer
The purpose of the silicon ring (See Figure Part 2) is to absorb vibrations and thus reduce false alerts. A thin film of ice may bridge over the silicon ring and/or sensor (See Figure Part 1) and false alerts can occur. Upon visual inspection, there may be no obvious obstruction with the sensor. Often, when the vehicle is inspected, the ice will melt, and all evidence of frost/ice would no longer be present.
Diagnostics should be performed but if no DTCs are present then ice bridging on the sensor was likely the issue. Verify sensor alignment and ring placement is symmetrical.