2017~2024 2020 CX-5 Aftermarket Remote Start Honking Horn

Hey, folks. I just got a 2020 CX-5 Grand Touring Reserve for my wife. It didn't come with remote start (except through the annoyingly-bad app), so we had an aftermarket unit installed. Now she merely has to hit the "lock" button on the key fob three times, and the car starts right up. The problem, though, is that the car honks the horn after the second time hitting the lock button, and then again after the third hit. I've disabled the option in the car's menu for honking the horn on lock, but it still does it. I contacted the installer, and he insists that it's not the fault of the remote start module he put in. He said this is definitely a Mazda thing.

Does anyone know how to disable this? It's very annoying to the neighbors when she has to leave early in the morning.

Thanks for your help in advance.
 
This is how the Mazda works. I don't know of any way to disable it. I had my installer give me a separate remote to use to start it. It means you have two fobs, but it doesn't honk. I have heard that someone here had their installer program it so "Lock, unlock, lock" is what would start the car. Hadn't contacted my installer to see if they could reprogram it to use the factory fob like that.
 
Thanks for your reply, Nathan. Our installer offered the option of a second key fob, too. But my wife can't keep track of one (she's already locked her keys inside the damned thing) much less two. I know about the "lock, unlock, lock" trick, but that seems too inconvenient, and a lot of wear on the power locks. It might be the only option, though.

I was hoping there was a hack of some kind.
 
If it's a Compustar/Idatalink module, it can be programmed for lock/unlock/lock. Horn will not sound. If you want it completely silent, you can disable the lock "chirps" in vehicle settings. I think the horn is a function of pressing the lock button twice that is baked into the vehicle programming. Avoiding that second lock press avoids the horn. I did my own install using the Weblink updater, but any installer should be able to reprogram it in a matter of minutes.

** In the Compustar setup, there are several options for door locking/unlocking sequences. I didn't really pay much attention to them since I use Dronemobile. But I think there is an option to avoid the unlock after pressing lock the first time.
 
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Thanks, Roguelego. I've already disabled the menu setting for sounding the horn on door lock, and the installer verified that the remote start module is not causing the problem. It's clearly, as you said, something baked into Mazda's programming that activates when you push the "lock" button more than once. I was hoping some computer genius who loves Mazdas had figured out a simple hack to solve this. But, in the end, if I have to reprogram the unit to use "lock, unlock, lock", then that's what I'll have to do, I guess.
 
You could always couple a cell phone based starter with your kit. I use dronemobile and it starts using the app with no honks.

Naturally there’s additional costs ($150 for unit + $180 for 5 years of service + install), but, you can start from any phone as well as an Apple Watch.
 
If it's a Compustar/Idatalink module, it can be programmed for lock/unlock/lock. Horn will not sound. If you want it completely silent, you can disable the lock "chirps" in vehicle settings. I think the horn is a function of pressing the lock button twice that is baked into the vehicle programming. Avoiding that second lock press avoids the horn. I did my own install using the Weblink updater, but any installer should be able to reprogram it in a matter of minutes.

** In the Compustar setup, there are several options for door locking/unlocking sequences. I didn't really pay much attention to them since I use Dronemobile. But I think there is an option to avoid the unlock after pressing lock the first time.
Can I do reprogramming myself? Everything I Google just brings up how to program a replacement remote. I'd like to be able to change software settings myself.
 
Which system do you have installed?

you’ll need a usb programmer for your device (usually $20-40).
 
You need the idatalink USB module. You download the program from compustar, connect your laptop to the remote start module via usb module and program the car (you can also disconnect the module from the car and program it at a computer).

Really easy, actually (assuming you can access the remote start controller box).
 
You need the idatalink USB module. You download the program from compustar, connect your laptop to the remote start module via usb module and program the car (you can also disconnect the module from the car and program it at a computer).

Really easy, actually (assuming you can access the remote start controller box).
Guess I was wrong. I just assumed they installed the DC3 as that was the newest. Found the module up under the dash, it's actually a cm900. According to the installation instructions, there is no option for OEM remote "lock/unlock/lock" to start the car. Not that I see anyways. Plus since I went with the cheap one button fobs, I'd have to buy the OP500 in order to program anything.
 
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