time delay relay for horns

Hello all. I did some reading on this forum hoping to answer a question I had and came across this thread: https://www.the12volt.com/installbay/forum_posts.asp?tid=57690&tpn=1&PN=1 It is 7 years old, but I was hoping to revive it as it is precisely what I'd like to do. Much to my chagrin, it is closed, though. I'd like to add a Wolo Model 417 horn to my vehicle. That said, my horn is also an indicator for when I lock my doors with keyless entry, giving me a short beep to let me know that they are locked. I'd like to use my factory horn for that beep and the upgraded horns when I actually press the steering wheel to honk in traffic. The thread I linked seems to suggest just that, but I'm a bit new at relays and was hoping to get some information as to just how that would be wired up. 2010 Mazdaspeed3 if it makes a difference. Thanks in advance.I'm a novice. Go easy on me.

If you are looking to have the Wolo horn work only when the ignition is on, you can wire a standard relay to run the Wolo only when the car is on. All other times, (on ACC only or car off) the factory horn would be engaged. Relay setup Pin 86 - horn (-) trigger wire Pin 85 - goes to ignition wire Pin 87 - connect to 12v Constant Pin 87a - not used Pin 30 - to (+) terminal on Wolo compressor Horn Trigger      blue      -      BCM, blue 24 pin plug (2), pin U Notes: The BCM (Body Control Module) is above the driver kick. Ignition      blue      +      ignition switch, 8 pin plug, pin A Notes: On vehicles with Smart Key, it is at the relay block, 6 pin plug, pin B. The relay block is to the left of the steering column. 12volts      orange (40A)      +      ignition switch, 8 pin plug, pin H Notes: On vehicles with Smart Key, it is at the relay block, 6 pin plug, pin A. The relay block is to the left of the steering column.

You know, I hadn't thought of doing it that way. That would also solve the dilemma, I suppose. It would eliminate the option of giving a quick tap while driving that only activates the stock horn, though. That said, I think I may be on board with this idea for ease and saving a few bucks. Good info.I'm a novice. Go easy on me.

I figured you would want to have the full electrical power for the air horns and not have to deal with troubleshooting a delay issue in the future. If the relay ever gave out, you would just pull it, pop a new one in and you are on your way again.

Makes sense. Still need to buy the components. I imagine the first thing I need to do is locate all of the necessary wires. I appreciate the help.I'm a novice. Go easy on me.

My pleasure. Good Luck!

Alright, I finally had a chance to really think about this and I still have some questions. Here is how I drew it up and how I imagine this working: Is that pretty fair? These two images assume that the ignition is on. If it was off, the ignition wire would have a break in it. Am I correct in that I would be piggybacking on both the ignition wire and the horn trigger wire? Basically, both of those wires would stay connected how they are from the factory, but in the middle, I'd run another piece of wire off of them to relay, correct? Additionally, in this setup, wouldn't the factory horn stay active even when the ignition is on? I think I'm okay with that, just trying to make sure that I am visualizing this correctly.I'm a novice. Go easy on me.

You make a great point. Initially, it sounded good in my mind. I even drew it out but neglected to notice the factory horn would still be active with the ignition on. Here is a revised formula (hehe). It involves 2 relays and cutting the blue factory horn trigger wire mentioned above. Relay 1 - Pin 85 - Ignition 12v Pin 86 & Pin 30 - Switch side of factory blue horn wire Pin 87a - Horn side of factory blue horn wire Pin 87 - to Pin 86 of Relay 2 Relay 2 - Pin 85 & Pin 30 - 12v Fused Constant Pin 86 - from Relay 1 Pin 87 Pin 87 - positive wire from Wolo compressor Pin 87a - No connection Since the only thing that links Relay 1 and 2 is the single negative wire, you can probably connect Relay 1 under the dash and Relay 2 with the horn under the hood. I believe this one will work a little better. When Ignition is On, the relay will be in "ready" mode. Once you press the horn switch, it will trigger both relays to remove the factory horn from the equation and trigger relay 2 for the Wolo horn. When the ignition switch is off or during Accessory use, Relay 1 remains off even when pressing the horn switch. It will still allow you to use the factory horn thru Pin 87a. Hope that makes sense.

Good. So I wasn't THAT crazy. I'll read this over a few times when I get some additional free time and possibly draw out a full schematic. Thanks for the response. The ignition 12v is simply piggybacked off of the ignition wire, though, correct?I'm a novice. Go easy on me.

That's correct. You would just piggyback off the ignition wire.