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There is no way to turn off the reverse park aid. If you are getting the steady error tone for 5 seconds when putting your car in reverse you most likely have a bad sensor. You will need the Jaguar IDS to pinpoint which sensor it is. Sometimes you can turn your key on and put your car in reverse and put your ear to each sensor. You should hear a clicking sound from each sensor. If you do not hear the noise then you may have a bad sensor or connection. If you do this make sure you have an assistant hold down the brake or use the parking brake when leaving the car in reverse.
ASE Certified Technician
12 years Ford Lincoln/Mercury Jaguar dealership as a technician and shop foreman reparing all makes