Okay, I'm attempting to install a Nautilus Compact Air Hone in my 2010 SS Sport. Following my logic and some outside advise I hook things up and bump the horn fuse to 20A.

Sweet sound a few times then nothing.

Pull the 20A and it's solid, hmmm?? Then I notice the set alarm 'horn' is no longer working as well as the replacement and I cannot "set" the cruise control. I can turn it on - dash indicator lights - but I cannot set it to speed. Of course "resume" doesn't work either.

I'm thinking relay, but things are vague in that area - little info that I can find.

Any ideas out there or is it time to visit Honda Service???
K_C_

 

have you tried putting the original horn and fuse back in to see if it works?

edit: Um... I'm leaning towards visiting Honda.

 

Haven't - but fuse did not blow. Why cruise set is out has me stumped.

 

Well, it could be part of a system that's tied to another fuse.

In a home electrical wiring... the electrical box has a master breaker that cuts ALL power. In homes with auxiliary electrical boxes that run from the main, there's a breaker in the main that will cut of the whole aux box. So it could be something like that in the Fit.

Or... it could be worse and you fried some wires (one reason not to bump up fuses).

 

Don't ever put over rated fuses in again. I'll just cause problems.

Check all other fuses and even the main fuses at the (+) battery terminal.

Edit: I just looked at the circuit diagram for you (service manual) and it looks like fuse #3 (20 A) at the battery terminal would be the culprit.

I suspect you have other things out too:
The main fuse #3 is for these circuits:

Fuse #23 10 A - MICU (＋B HAZARD), Hazard warning switch
Fuse #24 10 A - Horn, Security horn*5, Right brake light, Left brake light, High mount brake light, ECM/PCM
(BKSW)

Warning! You're probably driving around without brake lights.

 

Thanks for the words and insight Virtual. I'm slowly coming to the brake light conclusion and have realized I went into this in 'stupid is as stupid does' mode.

I'm going down to trace through things you've mentioned. I did look at the battery terminal fuses and they ARE alright [first thing I checked].

Did not make any changes to the original horn harness connector so all can/will go back. Now I know why the plug and play Accord horn is so popular around here.

I know there's a way - BUT...

K_C_

edit; actually just looed and fuse #24 never blew - it's the one I bumped - back in a bit.

 

I know that. The over rated (20 A) #24 fuse would allow the #3 main fuse to blow instead. Re check it.

 

Fuse #23 blew. Fuse #24 was the one I bumped.

Also found the horn relay [pg 22-8 FSM]. It sits above the under dash fuse panel on 2010 w/ Security. Any way to test relay?

I am thinking [fart] that w/ #23 smoked the relay is most likely ok. Going out to find mini-fusses and put things back to normal.

Also came across this: https://www.fitfreak.net/forums/fit-...nt-engage.html Seems like the cruise and horn might be married with relay - at least in an 07.

K_C_

 

My Accord horn works just fine.

 

Yeah-Yeah-Yeah!!! I know when to eat turkey [taken a liking to it actually], but not quite yet

All is back to OEM. Relay was fine, #23 blew taking out the brake lights, the street horn, the security horn, cruise "set" switch, and most likely stop lights.

#23 and #24 back to 10A and meeep meeep is back in operation along with everything else. Plug-and-play just isn't how I was brunged up.

I'll figure this out - with the help of this forum hopefully. I know it's been done, just that the info is scattered around town.

All welcome to chime in - even the ITYS's. Many thanks to VIRTUAL - cool heads prevail...
K_C_

 

Add a relay?

I don't know if the "return" (negative) wire from the horn goes anywhere else, but... if it doesn't, you could add a relay to power the horn instead.

Basically, the relay will draw power directly from the battery, and only use the original horn wire as a signal wire.

As for myself, once I get my Fit (next week, I hope)... I'm most likely going to take the PIAA Sport Horns I installed in the Pathfinder out. Put the stock horns back and put the PIAAs in the Fit... though, I now have to figure out how to use two horns in place of the one stock horn. hum...

 

Glad to be of help.

I think you'll need to add a relay which get "triggered" by the horn wire and the power source for the relay contacts would come from another source.

 

No idea as to how to do that. Relay sits on the power side of the horn. The horn I'm trying to use is a 12V - 18A unit. All I want to do is put in into an existing 12V - 10A circuit. I've discovered that 2 10A fuses are part of that circuit. I bumped one to 20A and blew the other 10A fuse.

So, and I know I'm NEVER to do this, what if I bump them both to 20A. Is the relay the next thing to take a fall? How are they rated? Might I simply upgrade the relay??

If I go with a separate relay how in the hell do I wire it in so the wheel horn button makes it work???
I'm seeing lot's of hot lobster and cold beer this weekend.
Horn can wait - meep meep.
K_C_

 

Horrible idea. Never put an above-rating fuse in a circuit. The fuse is there to protect the wiring among other things. The correct solution is to add a 12V relay that can handle 18amps (or more) through its contacts.

Basically, connect the power leads for the relay into the circuit in place of the existing horn. You then run a heavier gauge wire, WITH AN INLINE FUSE, from the battery to the normally-open (NO) switched relay contact, then from the other side of the switched relay contact to ground. When you press the horn button, it energizes the old horn circuit, which closes the relay, which allows higher current to flow directly from the battery to your new horn. Relays pull very little power themselves, so this should not affect the fusing or wiring for the existing horn circuit.

Your local auto parts place should carry suitable relays. These are normally used to add high-power offroad lighting or similar to vehicles. Look around that section of the store.

I'm surprised that your horn didn't come with such a relay in the package, since it's an aftermarket add-on anyway.

Here is a table showing the gauge of 12V wire you'll need, based on amperage and distance from the battery.

Here is an article about wiring aftermarket stuff to your car with relays.

 

Many thanks Steve,
So the hot lead I see at the OEM horn is going to go into a new relay post #86. My guess is that a four pole relay is standard numbered.
#85 goes to the frame, #30 goes to the "+" post on battery and is fused @ 20A and #87 goes to the new horn and it too is fused @ 20A.
The new horn is grounded to the chassis.

That seems simple enough, now why didn't I think of that NOT!

*****************************************

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Once known as Decoration Day it inspired the following:

We cherish too, the Poppy red
That grows on fields where valor led,
It seems to signal to the skies
That blood of heroes never dies.

To their sacrifice we owe our Freedom - take the time to remember them and honor all who served.
K_C_

 

I guess it hasn't been stated clearly enough yet.

Never put fuses rated higher than specified. That means never. Fuses are a fire prevention device.

If your car burns to the ground and the insurance find out that the wrong fuse was used then your out of luck.

 

No No No VIRTUAL - honest - I have learned my ways - read post #15 above - I'm trying to figure the hook-ups to a new 20A relayed circuit to blast my horns. Right now it's back to OEM all around.

You got me out of the mindset totally. I was going down one of my "what if" - "the devils advocate" things, that's all. Promise.

SteveInNC set me straight on the extra relay and how that works. I'm using the existing OEM horn circuit to trip a new relay on a new 20A circuit.
Like you said.

I almosted smoked an Audi Fox years back by hot wiring the radiator fans - she was smokin'!!! Someday I'll get over this tendancy...
K_C_

 

Cool! I just wanted to make sure.

 

Yes, I had to install a relay to power a pair of PIAA horn on my 09 Fit. The thin single wire from the stock horn will not be enough to power both horns. The single Accord horn is plug and play but it does not sound as good as two high & low horn. The battery powers the horn with a 20 amp fuse in between the relay and the battery.

 

Doh, I was hoping to be lazy and not have to worry about adding a relay.