The supplying dealer used non-approved parts on my car - how do I ensure this doesn't invalidate my warranty?

I've recently purchased a new car from a main dealer and paid for dealer-fit front and rear parking sensors. A week after purchase, it comes to light that non-manufacturer approved sensors have been fitted - even though I had specified only approved parts to be used. As mentioned in several places in the handbook, this will affect the warranty if the sensors cause failure in other parts of the car's electrical system. The dealer is adamant there is no problem and no issue. On appeal to manufacturer for help, they've recorded that the car has been fitted with non-approved sensors and they have stated the warranty position. Any ideas where I can go to for a resolution as other dealers may well refuse warranty work because there's a black mark on the vehicle.

Asked on 11 October 2017 by laurie Jeffreys

Answered by Honest John
Write a letter to the supplying dealer principal stating that because he fitted non-OEM parking sensors when you specifically ordered the car with OEM sensors, you hold him fully responsible for any electrical problems that could have been caused by the non-OEM sensors for five years. Send the letter by Post Office Special Delivery, keep a copy and staple the certificate of posting to the copy so it becomes a 'matter of record'. Then make sure you keep the copy letter somewhere safe.
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