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Horn blowing relay

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I just purchased a 2001 Boxster base and the horn deosn't work. I followed suggestions from this forum, fuse was ok but when I changed the relay the horn worked until I started the car, now it no longer works again. I assume I am blowing the relay. Anyone have any suggestions?


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I just purchased a 2001 Boxster base and the horn deosn't work. I followed suggestions from this forum, fuse was ok but when I changed the relay the horn worked until I started the car, now it no longer works again. I assume I am blowing the relay. Anyone have any suggestions?



First, welcome to RennTech :welcome:


Do not be so sure the relay is failing, recheck the fuses first.  If your car is killing relays, it most likely has a dead short in the horn system which you will need to trace.

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FWIW, German cars are all wired to Bosch standards, and in this case the horn never works with ignition off by design.  If it does, something's wrong and I'd think it more than a missing ground, as clearly it's getting one to work.  It's also getting a positive, which should not be the case.

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