Car Horn Upgrade.

[Polywobblydriver]

I'm a DIY amateur so please help. Can a stand alone "Plug and Play" set up be made from scratch to upgrade a single tone horn to a High/Low horn?
I don't have the confidence or knowledge to 'chop' into the existing wiring harness and want something reversible if the idea doesn't work. So, could I wire the two horns in parallel taking the four wires down to two terminals, both positives together and both negatives together. This all built onto a bracket that I simply connect to the original two wires from the factory fitted horn?
I have been told by the wise people on this website that as long as the total Amps for BOTH horns together isn't higher than the fuse fitted I should be good to go. Odd thing is there doesn't seem to be a relay for it fitted from the factory?
I will be grateful for any advice.
(2018 Dacia Logan MCV, UK)

 

[Spoon]

You say that there are no additional electronics on the new horn, so wouldn't both horns go off at the same time if you wired it the way you say.
You say there are 4 wired on the new horn. I presume 2 wires for the high and 2 wires for the low.
You could always give it a try by wiring the 2 sets together and then wiring them to a 12V supply. Saves you taking out your old horn if it doesn't work how you want it to.

 

[brianmoooore]

It's quite possible that the wiring for two horns is already there. A lot of models have single horns on their 'basic' models and twin horns on the better equipped versions.

 

[Polywobblydriver]

You say that there are no additional electronics on the new horn, so wouldn't both horns go off at the same time if you wired it the way you say.
You say there are 4 wired on the new horn. I presume 2 wires for the high and 2 wires for the low.
You could always give it a try by wiring the 2 sets together and then wiring them to a 12V supply. Saves you taking out your old horn if it doesn't work how you want it to.

I haven't got a new horn yet. Ah, I never thought of testing on a spare 12v battery. I was asking as I am curious if I could build one myself from spare parts and be able to simply unplug and unbolt it if there was issues. I was just worried if I double the horn would it cause other issues in the electrical system?

 

[Polywobblydriver]

It's quite possible that the wiring for two horns is already there. A lot of models have single horns on their 'basic' models and twin horns on the better equipped versions.

I haven't had a chance to look in the wheel arch yet. Mine is one of the higher trim levels. Being a budget brand car (Dacia) I suspect all of the cars are single horn.

 

[w0z]

I haven't had a chance to look in the wheel arch yet. Mine is one of the higher trim levels. Being a budget brand car (Dacia) I suspect all of the cars are single horn.

What makes you think the horn is in the wheel arch? Have you seen it there? I thought it was elsewhere but I don't want to mislead you if I'm wrong... (have a look below or around the battery).

Also if there is no relay adding another electromechanical horn (depending on current and inductance) could burn the horn contacts, which would make them unreliable. (easily solved with another relay)