Archived Message
RV8 Fuse 12 blown
Since I have purchased my RV8 earlier this year, I have problems with fuse no 12 blowing. It seems to be linked to the horn, each time I push the horn switch on the steering wheel the fuse blows, everything else on this fuse does not seem to cause a problem, I can play the radio and open the tailgate just fine, but as soon as I apply the horn, the fuse goes. Has anybody else seen a similar problem on their car and are there any suggestions what the problem might be, respectively how I can fix the problem? Thanks,
Helmut Reder
26/08/2012 @  21:24
Under topic: RV8
Archived Reply(ies) received for this Message
RV8 Fuse 12 blown
Hi Helmut,

I don't have any first hand experience with the horns on the RV8 but generally speaking, if the fuse blows when operating the horn I would suspect one or both of the horns, the wiring from the fuse to the horn or the fuse itself.

I would start by disconnecting the horns one by one. If the fuse stops blowing with one disconnected then you have a short (or decreased resistance) in the disconnected horn. If the fuse keeps blowing with both horns disconnected then you have a short in the wiring loom between the fuse and the horns. The latter could also indicate a bad relay but I don't know how common it is for a relay to fail in that way. As the horns are at the front of the car and therefore exposed to the elements, it is not completely surprising that they can fail like this.

I had a similar experience with my condenser fans where corrosion had led to a fan starting to seize up which in turned caused it to consume more power. This made the fuse blow and a previous owner apparently responded by installing a larger fuse. The end result was that the actual wiring burnt out somewhere so I had to redo the wiring from the fuse box to the fans.

The moral of this is: Car manufacturers are cheapskates (and concerned with weight) so they will typically choose the lowest gauge wire the load requires. Don't put in a larger fuse. Hope this helps,
Erik Persson
27/08/2012 @  17:14
RV8 Fuse 12 blown
Hi Erik,

Thanks for the advice, I will try to disconnect the horns over the next weekend and check if any of the two is causing the issue, I will let you know if I was successful. The wiring leading to the horns seems to be fine based on a visual inspection, but it could of course be damaged at another location which is not visible. Thanks,
Helmut Reder
28/08/2012 @  05:54
RV8 Fuse 12 blown
Perhaps a silly question, but you are using a 15 amp fuse, are you?
Chris Hunt Cooke
29/08/2012 @  04:33
RV8 Fuse 12 blown

yes I have been using a 15A fuse, did not want to go higher up to avoid any potential damage to the wiring harness.


Helmut Reder
30/08/2012 @  06:27
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