[BBRam]

If you are in reverse with the door open, the horn will sound. Also if it is not quite in park and you open the door, the horn will sound.

Not sure if this is what's happening though?

 

[xploretx]

That alarm is a part of a safety recall. The dealer programs the FCM. I didn't have the alarm until I replaced my FCM.

Pete

 

[AKmega6.7]

Can this be removed?

 

[BBRam]

This may help?

http://www.cumminsforum.com/forum/3rd-gen-tech-articles/4724-reverse-alarm-disabling.html

 

[AKmega6.7]

sweet thanks, I might have to give that jumper wire a try. Did you?

 

[Drag-n-Fly]

If it is the FCM the seatbelt jumper won't fix it. If it was taken in on recall and flashed to the computer the seatbelt jumper works.

 

[2500 Grunt]

Since I have owned mine it has been in for warranty work and afterward I did the seatbelt jumper fix and it still does it.

 

[mzcummins]

Try this, some say it works, some say it dosen't, I did it on mine and it turned the seatbelt chim off but I don't know about the backup honking.

Seatbelt Chime - Diesel Truck Resource - Wiki

 

[AKmega6.7]

I disabled the seat belt dinger myself using different instructions, I will try that for the reverse horn. i just hope it doesnt turn my seat belt dinger back on