Horn sounds weaker than usual

tell all that works and does not work not just the bad
electric and fuses run off huge power buss.
even 10 things off 1 fuse
so telling it all makes the job 10x more easy see?
dim head lamps high and low beams?
horn dead.
but does car start run and drive,???

is key dead? engine dead. , heater blower dead
radio dead. ???????? key starter motor sounds strong and fast cranking the engine to start it?

Could be a bad horn relay. Cheap to replace usually.

Relay sounds like its working, horn is located between grill and radiator. And it sounds like horn is bad

your remote is picking up another signal some place and your cars being haunted by it
reset alarm settings
now the other problem is your battery is getting weak loosing its charge because its constantly on simple get charger to trickel charge system or replace battery

do you hear a click sound from a relay when pressing on horn button? most likely is underhood. if so,locate the horn(s) and test voltage with a test light or DVOM at the horn + side. if both have voltage,check - side.(ground).if both are correct replace both horns.

It's possible that the horn exit passage is plugged with debris, but these things are usually a sealed unit which must be replaced. There should be two horns that blow together located one on each side of the radiator--if one is dead, the sound is greatly reduced. Some horns have an adjustment screw that will optimize the sound level. Hope this helps!

Actually you use the horn relay a lot! At least 3 times every time you get lock/unlock your car (6 toots, 2 toots for lock and 1 for unlock right?) ... You just said: "as i clicked my car to lock. It got weaker and weaker until it stopped working" Buy a different brand relay (preferably one not made in China, pay more) and don't expect they WILL last a long time the horns take a lot of power and they have a very dirty feedback to the relay un-like lights. You can dis-able the toots by reading your owners manual.

The battery may have just been replaced, but have you checked the voltage lately?

This sounds like it may have a charging problem.

First, put the battery on a slow charger over night, and see if it will start the next morning.
If it sounds strong, but get weaker after running for a while, you'll want to check the output of the alternator.

You can take your Venture to a local autoparts store, and ask them to run a charging check for you.

Sounds like you may have corroded terminals on the horn itself.

Find the horn in the engine compartment - remove the wire connected to it - clean the spade terminal with some sand paper and push the terminal back on. If that doesn't work you may need to remove the horn from the car and clean up the earth connection, i.e. where the horn is attached to the body work of the car to get a good electrical contact.

Wow man, it sound that you need to replace the car... too much problems, sell the car and buy better one.