Wireing to horn

[Glynhouse]

I would like to fit my old Maserati air horns to the D3, got them working on the bench OK (1963 models).

Will power them through a relay no problems but where do I get the horn wire from ?
Have the grille off - isn't that easy on these things ! the horn has 2 wires feeding it from the loom, I am used to one and an earth.
Would like to pick up the active from near the horn and have a two way switch inside, one to activate the standard horn and the other to the relay to power the air horns, same as I have always done.
Am I likely to upset the electronics ? will the car know the horn is disconnected as I imagine the relay will not draw anything like the power of the existing horn.
I could rig another separate button to activate them but would like to use the original horn button.

Thanks for any suggestions.

DD

[rufusking]

Cant see it causing any major issue, probably just log a fault.

When bypassing the accessory relay (power saver relays for the cig outlets) no major issue just logs a fault which doesn't seem to cascade to anything.

[LandyAndy]

Personally I would wire them seperately.
You dont need issues with the ECU that runs the imobiliser etc.Also should you ever need to put the vehicle over the pits you will need to return it to standard as these days there is an ADR for the horn tone(get heard blowing the horn could invoke a sticker???).Also,the horns are obviously of sentimental value,seperately wired would make an easy remove without re-instating the originals when its time to replace the vehicle
Andrew