Volvo v40 alarm will not turn off with remote.How can I turn it off manually.It is not the fob battery.Car will start with the key but alarm keeps sounding.Neighbours are unimpressed.Have tried disconneting/reconnecting battery and locking/unlocking twice to no avail.

these links should help
Free Keyless Remote Fob Entry programming instructions procedures for all... How to Set Up New Key Remote To Your Car Lost Or Stolen Remote

Hi there my name is Brandon I am a electrical and mechanical engineering technician did you program the th... system and the key and what bout the ecu (is engine control unit it has to be problem) ecu is probably not sending start to cam and crank sen... I would put money on it or the th... system not taking the keys code for it

retry replacing battery new doesnt mean cant be defective if it is good than fob needs a relearn different cars have different relearn that you can perform but if the fob has other features such as start that will have to be done at dealer ----
Free Keyless Remote Fob Entry programming instructions procedures for all... look up your vehicle and will have instructions one how to program fob --will also tell if need to be done at dealer

The dealer usually has a contractor that deals with remote entry systems on scheduled days. Most places like carmax do too for about $75-100. Try carmax first. I'll bet you'll save money.

The remote receiver inside the alarm itself is malfunctioning.I would say have it repaired but would probably cast as much as a new one.

It's your built in security alarm , have you changed the battery lately ? The procedure to reset it is: Unlock drivers door with key, then use key fob in unlock door mode, put key in ignition switch, foot on brake , transmission in park or neutral and clutch depressed (If applicable )

Inside the key fob are contacts that get dirty, both the electric side and the push button side, carefully clean them both.

You should be able to disable the alarm by putting the key in the door and turning it, or by putting it in the igintion switch and turning it. One of the two should disarm the alarm. If that will not work, then you could disconnect the battery, call the dealer and get a key fob for the alarm system.

Turn off the car and turn it back on, then check for any alarm buttons. Press those a few times, and try it. Also try to manually unlock the doors with the key.

open door. when alarm goes off put key in ignition and turn it on start car. this should disarm the factory alarm.