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Weird wiring

I have a 2001 ford escape I recently bought and the factory radio is funky. It will switch presets and modes when I turn on my blinker, or put it into drive or park, or put on the brakes. The only thing I can think of is that wires for the radio and for the taillights are bad and touching somewhere or something like that. If that is the case, how can I find and identify those wires?
Thanks for your help!

It might not be a problem with the wiring. It might just be the radio is defective. Car Radios have parts in their power supply circuit called “capacitors” which are there to reject electrical interference from other things in the car turning on and off, like blinnkers, stop lamps, xmission signals, etc. All the power connections are tied together, so if one thing causes interference, all the other things like the radio get an interfering signal on the power supply input. Hence the capacitors. But these interference-rejection capacitors sometimes dry up and stop working. I expect that is the problem.

Buying a new radio is probably your best solution. The aftermarket ones are inexpensive, and the ones with the USB inputs are a great way to listen to mp3 podcasts. You just load up a USB memory stick with whatever programming or music you want, and listen to it in your car. It’s way better than the factory radio.

It’s possible your radio is ok, and your wiring is the problem. More likley if your car has been in an accident. But it still probably isnt the problem. You’d have to get someone experienced and who has the required electronic tools to trace out the wiring diagram for your car, to know for certain one way or the other. If you want to do it yourself, you’ll first need to study up on how to read car wiring diagrams. I’ve seen good books for that at my local Barnes & Nobel in the transportation section.

Cars electrical systems are full of spikes, surges, voltage drops, ignition noise…Chances are it’s the radio itself that has a bad input filter and has become super-sensitive to to normal automotive conditions…I would replace the radio first…

You’re describing of the early symtoms of the PRNDL (prindle) switch as us techs call it starting to fail. Ford calls this part the Transmission Range Switch. This switch not only informs the main computer what gear the transmission is in, but it also informs the body Generic Electronic Module what gear the vehicle is in. The radio is usually the first component to act up. Then other circuits start to act up. When the power window or windshield wiper circuits start acting up, then you’ll know for sure the problem is with the PRNDL switch.

Tester

I agree with the other posters. The only thing that I would add is to make sure your new radio plugs directly in to your vehicle’s wiring. Any other type radio needs to be left on the shelf.

I agree with Tester, make sure you check out the PRNDL switch before buying a new radio.