Sprinter 3500 chassis replacement horn?

[Heffy]

We just traded in our 2017 Class C Coachman Prism 2150LE for a 2018 Class B Winnebago ERA 170a which are both based on the Sprinter 3500 chassis.

On the Prism I installed a set of horns from a Ford F150 that worked great. I'm thinking about swapping out the Vespa horn on the new RV with a Stebel Nautilus like I have on my 2008 BMW K1200GT motorcycle, but where in the heck can I find 12v in the engine compartment to power the relay? Or am I forced to run a wire through the firewall and into a fuse panel???

Does anyone have first hand experience on this type of install? So weird not having the battery in the engine compartment...

Thanks!
Jeff G.

[Winterbagoal]

Can't you reuse the existing horn power/wiring? Or, are you adding to the existing Vespa horn (good analogy)?
I've been trying to figure out the horn thing too, so I'll be watching for new ideas. I was thinking of swapping in a Wrangler horn, but I'm not sure if one will fit where the existing door buzzer horn sits.
The Agile Off Road kit reuses the existing power/wiring, but it's pricey and requires some driling.

[604eholston]

I replaced the horn on my Winnebago Era (2015 sprinter chassis 3500) with a battery operated air horn. I used the wiring from the OEM horn. Had to run some extra down near the bumper to find a place to mount it.

[Heffy]

Originally Posted by Winterbagoal

Can't you reuse the existing horn power/wiring? Or, are you adding to the existing Vespa horn (good analogy)?
I've been trying to figure out the horn thing too, so I'll be watching for new ideas. I was thinking of swapping in a Wrangler horn, but I'm not sure if one will fit where the existing door buzzer horn sits.
The Agile Off Road kit reuses the existing power/wiring, but it's pricey and requires some driling.

Well the Stebel draws considerably more juice than the factory "beep-beep" Euro horn or the F-150 horn, so it needs a power feed. That's where the relay comes into play...

Nothing but a single horn fits into that plastic box cavity - aluminum diagonal cutters are your friend

[Winterbagoal]

Originally Posted by 604eholston

I replaced the horn on my Winnebago Era (2015 sprinter chassis 3500) with a battery operated air horn. I used the wiring from the OEM horn. Had to run some extra down near the bumper to find a place to mount it.

Battery operated, as in vehicle underhood battery? Don't know if I need that much volume, but it's worth a look.
Yes, as you both point out, there's not much room where the original is mounted.

[604eholston]

Winterbagoal, yes, used the original wiring and relay from the chassis battery. Have you listened outside your coach to the OEM horn? I know my hearing is bad but I have had someone toot mine while I was standing near the left headlight, it was a sad awakening, volume woefully inadequate. This is why I bought the air horn.

[Winterbagoal]

Originally Posted by 604eholston

Winterbagoal, yes, used the original wiring and relay from the chassis battery. Have you listened outside your coach to the OEM horn? I know my hearing is bad but I have had someone toot mine while I was standing near the left headlight, it was a sad awakening, volume woefully inadequate. This is why I bought the air horn.

Copy that, and thanks for the insight and advice.

[Winterbagoal]

Forgot to add, yes, I've heard it, and it sounds like the Roadrunner's "meep, meep". Just dire.

[kenandterry]

Originally Posted by Heffy

We just traded in our 2017 Class C Coachman Prism 2150LE for a 2018 Class B Winnebago ERA 170a which are both based on the Sprinter 3500 chassis.

On the Prism I installed a set of horns from a Ford F150 that worked great. I'm thinking about swapping out the Vespa horn on the new RV with a Stebel Nautilus like I have on my 2008 BMW K1200GT motorcycle, but where in the heck can I find 12v in the engine compartment to power the relay? Or am I forced to run a wire through the firewall and into a fuse panel???

Does anyone have first hand experience on this type of install? So weird not having the battery in the engine compartment...

Thanks!
Jeff G.

A recent visitor to our place had their motorhome built on a Mercedes 3500 chassis. I’m going to assume the engine compartment is the same for a moment…….

Do you know how you would connect jumper cables in the engine compartment?
I know the battery is under the seat, but there is a major 12 volt connection point in the engine compartment with a red plastic covering, specifically for jump starting or battery boosting. Your owners manual should show you where it is.
Saying it’s under the hood isn’t much help to you…….but it is.

It’s red number 3 on the right in this photo.

[Good To Go]

They do make a replace horn that is loud. I saw the video, the guy posted on his Sprinter 3500 replacing the horn. Not sure where I put that video.
Look up video of horn replacement on sprinter.
Steve

[bigb56]

Agile Offroad has a plug n play kit for $100 or so. https://agileoffroad.com/product/agi...ter-2007-2018/ I wired my own from Amazon, this one: https://www.amazon.com/GAMPRO-Inches...%2C265&sr=8-27
I ran the power wire from the fuse box down by the OBD port which is always live, mine had a few extra spaces. Then I connected the relay trigger wire to the OEM horn. Mounted the horn on the cross member in front of the radiator, pointed slightly downhill to keep water from collecting in it and I put the relay high and dry under the hood. Now both horns sound but the Gampro pretty much drowns out the factory beep beep.

[LAT-LON]

I struggled with the Sprinter OEM horn as well. Finally settled on a Bad Boy horn from Amazon, but it's available from multiple sources. Hardest part was finding a location for the new horn and adhering to the standard KISS principals.. The best place ended up being just below the radiator hose on the right front chassis. I removed the existing horn and extended the original wiring to the new horn location. The Bad Boy was mounted using the supplied hardware. Attached photos aren't all that great but show enough to help understand.

[bigb56]

How does the Bad Boy work with the Sprinter 10 amp horn circuit? According to the specs it uses 14 amps, have you blown the factory fuse yet?

[LAT-LON]

Fuses are typically underrated and rely on current over their rated value to heat up the fusible link to the point that it melts. That heat buildup usually takes time, unless the current is really excessive. Haven't had any problems yet, but the 10 Amp fuse should hold for as long as I might need to use the horn. If I have to lay on it that long, blowing the horn isn't going to help the situation. If we survive the incident and the fuse does blow, I'll replace it with a 15 Amp .