Horn goes off continuous on reconnecting neg terminal

[blz6662]

From my previous post you will know I'm underway with some sill repairs therefore battery disconnected - anyway needed to move the truck into another position in the workshop for better access so reconnected pos lead then neg lead and the horns blasted continuously (not beep beep as an alarm). It has a sigma alarm fitted which worked perfect along with the central locking and has a separate siren.

Used the blip and locked then unlocked the truck, horn still going! - Disconnected neg lead off battery pulled the fuse and reconnected neg lead then blipped the alarm locked then again unlocked key in ignition starts perfect.

Have not tried to put the fuse back in 'live' yet.

So guys, any ideas. tips, clues etc.

Dare I use these letters on this forum - eek here goes - on my BMW535i I use a CTEK Battery saver / Power source to keep the ecu live when I disconnect the battery, so should I do the same on the disco - 1992 3.5 efi - ecu 14cux.

Help I've got enough jobs to do without this.

Cheers

[teabag]

Maybe the horn push button is stuck, I'd remove the horn fuse B5 as a temp measure, it's a simple circuit to trace, a 12v supply to the horn push then to the horns which are then earthed.. Your D1 efi ecu doesn't have volatile memory so there's no need to maintain a 12v supply with your CTec.

[CJ1]

Sounds like the alarm is arming itself. If you have a remote fob try disarming it. Or once battery is re connected, shut everything and lock and unlock it.