Battery is dead. Clicking sound from under dash. I tried jumping. on 2003 Honda Odyssey

When I connected the jumper cables the lights came on and the horn starting honking. I couldn't shut it off with the fob. I disconnected the jumper cables and everything shut off.

Asked by for the 2003 Honda Odyssey
Factory alarm or aftermarket?
Going to do the same thing when you replace, charge or jump the battery, try locking the doors then unlock with fob and disarm alarm, have a battery draw test performed. Since it is factory alarm maybe the Honda tech. here will help.
2 more answers , 1 more comment
poss battery is shorted internally.
replace battery to far gone, or take over your local auto parts and try charging it, they do it for free
Hook the battery up , and then(while ignoring the annoying alarm) calmly go to the drivers door and lock , then unlock the door with THE KEY . If no other problems with system exist , then that will disarm it. Recommend charging the battery first , not trying to jump it.
Qualified Local Honda Shops
Qualified Honda Shops For This Repair
921 N Parker St
Technical Ability
Tools & Equipment
Customer Service
Customer Amenities
(714) 486-0367