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Need help asap. Replaced a factory headunit today. It was a factory single DIN underneath and a tv screen on top. Now it just has a D/DIN headunit. Everything works fine but everytime you turn the lights on it blows the brake light fuse under the bonnet.

There were three wires left on the plug that had the power, grnd, acc and front speakers. One wire is yellow and the other two are black(the black wires run into the same point on the plug) My guess is this is an illumiation wire for the old headunit and the 3 wires have to be joined together to complete the circuit and stop the fuse from blowing.

Need a reply asap. tonight would be good.

Thanks all

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Use a test light (if possible) to find the illumnation wire (this will show +12V when you turn the headlights on) then insulate it and dont use it. If it is joined together with the earth wires you will blow fuses all day. Dont even use the earth wires from the aol head unit you are better off earthing to the body (chassis) of the car this will also help reduce the chances of engine noise. NOTE the illumination wire will show an earth when the headlights are off then goes +12V when you turn them on.

If you still have problems go to my website and get my phone number I will be available till quite late.

Good luck.

Leon

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