Added horn, now blowing the fuse

qrk · June 20, 2018

I wasn't satisfied with the sound level from the factory horn on my 2018 Sierra 1500, so I bought a Wolo Big Bad Max. I wired it in parallel to the high note factory horn, splitting it off the normal connector behind the low note horn. I suspect but haven't proved that the factory horns are wired parallel to start, so in theory all three should be in parallel now. I tested it several times and it seemed to be working fine for a few days, but this morning came out to find the fuse was blown. The wiring all looks ok. I switched out the fuse and it worked again. Is it just overdrawing with a third horn on the circuit?

austingta · June 20, 2018

Horns are high draw. Add a relay.

https://www.amazon.com/Absolute-RLS125-12-VCD-Automotive-Relay/dp/B0002KR9GG/ref=sr_1_5?ie=UTF8&qid=1529506237&sr=8-5&keywords=12v++relay

qrk · June 20, 2018

I was hoping not to have to rewire the entire system back to the fuse box or add a second switch. Is the factory wiring going to be able to handle that? Just makes me concerned that if it's blowing the fuse and I bypass it, could it cause bigger problems?

Eddie 70 · June 20, 2018

3rd horn drawing too much current for the stock sized fuse. It is used for the 2 horns. Putting the 3rd horn in parallel does not reduce the total current the fuse sees.

austingta · June 20, 2018

Just wire the new horn to one pole, 12v from battery to another and the source wire to the third. Follow directions. Works like stock. That's what they're for.

qrk · June 20, 2018

I'd prefer not to run wires all over the place or get too deep into the fuse box. Doesn't sound like there's a clean and simple installation like I was hoping for. I may just disconnect the high note horn and use the air horn as a replacement for one of the stock horns rather than as an addition.