Magnificant description and guide. I am struggling to find a fuse holder for the mercedes fuse box that looks like the one you are showing. Would you have a part number from some shop or a link ? Thanks again for taking time to put this video together
thank you. here is the fuse holder that worked for me. www.amazon.com/gp/product/B0BB2BWZ5K it currently shows 'out of stock' but I think with the part numbers listed. you can find a substitute.
Loved the video so much that I just finished following your install instructions, mostly, on my 2020 MB Sprinter chassis RV. I mounted the relay on the opposite side of the engine compartment and used Fiamm horns instead of Hella. But now none of the horns operate. Do you know which fuse or fuse/relay controls the original horn? None of my fuses are labeled including in the "fuse assignment supplement" booklet.
thank you. in the VS30 Sprinters (2018 and up), there is no fuse for the horn. it is entirely controlled by the SAM (signal acquisition module), one of the many control modules of the van. the SAM also provides an electronic equivalent of a fuse - but nothing you can change/reset. did you cut the wire into the original horn to connect the wire toward the relay? or did you somehow tap in without breaking the original wire? it's this wire where I would start troubleshooting. do you still get +12V when you honk the horn? also remember the ignition needs to be on for the horn to work. feel free to reach out via email (RU-vid about page) and we can discuss in more detail
Love your videos! I do have a question however, how did you MacGyver a load side of a fuse holder into that grey block? Does it come out? Also I'm having hard time finding a correct "socket" for that fuse. Totally like the idea of having two different sounds of horns, louder for driving and a quiet one for chirping.
thank you 🙂 the entire fuse block holder (the "main frame where all the different colored blocks are inserted into) is held in place with a single screw at the bottom, towards the passenger's seat. I loosened that screw a bit, just enough to move the entire frame up a bit. this gave me enough clearance to wiggle the holder in from underneath. I'd say it was a #6 difficulty on a scale from 1 to 10. this is the fuse holder I used: www.amazon.com/gp/product/B0BB2BWZ5K
Thank you for the video 🙏🏼. Did you have to take out the fuse box in order to install the new wire in fuse space 27? Can you explain how you did that installation?
thank you. No, I did not take it out completely. I removed the screw at the back (towards the seat) and then tilted/lifted up the box tray just enough so I could slide in the new holder from the bottom. there is plenty of space below the box so I could almost insert the new holder even without tilting it up. It just made it so much easier with the one screw removed and a little more wiggle room.
I beg to disagree with the need for a relay. The factory horn is 10amps. I find it hard to believe that Mercedes would use 16guage wire, rated to handle only 10amps at 12VDC on this circuit. They tend to error on the side of safety, so I'm guessing it is 14 gauge wire. The hella horns draw 11amps, so 14 gauge is sufficient.
According to Hella's documentation, the factory horn draws about 5A which matches the wire gauge. the new ones, combined, draw about 12A, again, as per Hella's specs. Also, the wire gauge is just one part of the equation. in the VS30 Sprinter. the horn does not have a dedicated fuse. it is protected by an electronic circuit breaker of one of the control modules. and even if the Hella power ratings are a bit optimistic, current is at least doubled (going from one old horn to 2 new ones). I feel better keeping this away from the control modules.
I like your method "the right way" of installing your aux. horn kit. I intend to do the same. Got the horn, but where did you get the connector to go in the fuse box? Thanks for all of your video's. I have incorporated a few of then on my 2021 Revel. When I do a search for it I get those fuse tap contraptions that go in a populated fuse slot and piggy backs a second fuse.
Hello, you are installing correct, i like your work. But i have a question about the relais: is it not better to install a quenching diode to eliminate the high voltage, when the extra relay switched off?
@@orange13 Hi "Orange13?", thank´s for your answer. And now i have another question about the horns. They have also an electric magnet inside, which will be switched with the frequency of the horn (may be 350 HZ). Is here no quenching diode necessary?
@@helmuthahn3545 one horn is 400Hz, the other one is 500Hz. I'm pretty sure they don't have a quenching diode built in. While I'm not a car electronics engineer, I know that any given car is full of inductive loads: the (original) horn, the motors in the mirrors, windows, seats, countless step motors and actuators. I think car electronics these days are well protected against any voltage spikes from switched inductive loads. Also, and for the new horns specifically, with the relay, they are more or less directly connected to the battery/12V bus without a lot of sensitive electronics in the path. these horns are being used in cars/vans by the millions and they are not causing any issues.
