My polo 1.4 horn does not stop when i switch on the car

Fuse #40 on one model.. Look here for your year:

https://www.google.com/search?q=VW+polo&ie=utf-8&oe=utf-8#q=vw+polo+fuse+box+layout

Horn relay could be bad too.

The problem will no likely be the horn. Go to the horn and have someone try to sound the horn, if the 12 volt test light doesn't light up then you have a problem in the contact drum under the steering wheel called the clockspring.

1) Check for power to horn unit with steering wheel horn switch depressed. If power present, replace horn unit.

2) Check horn switch operation. Repair or replace.

3) Check continuity from driver's horn switch mechanism and horn wiring. If faulty, then trace wiring back to fuse box and relay assembly.

Make sure you haven't skipped any steps before attacking the fuse box issue.

check your fuse first. if fuse is fine then is probably the horn relay

2002 VW Polo

The fuse no.# 52 - F52 (20A yellow) = Horn, windscreen wash / wipe system

Synchronization
When
Key buttons operated repeatedly while vehicle out of range and system becomes inoperative.
How
Polo: Press key unlock button for approximately 1 second. Golf/Bora: Press key lock or unlock button for approximately 1 second. Manually lock or unlock vehicle. System should now lock or unlock vehicle. If not, carry out programming procedure.
Programming
When
Key added or replaced. System malfunction.
How - Polo
Keys can only be programmed using diagnostic equipment.
NOTE: A maximum of 4 keys can be programmed.
How - Golf/Bora
98MY
Keys can only be programmed using diagnostic equipment.
NOTE: A maximum of 4 keys can be programmed.
How - Golf/Bora 99MY


Switch ignition ON. Insert key to be programmed into driver's door lock. Lock vehicle manually. Press lock or unlock button. Wait at least 1 second. Press lock or unlock button again. Vehicle horn sounds to indicate correct programming. Keys can also be programmed using diagnostic equipment.
NOTE: A maximum of 4 keys can be programmed.

alot of cars have differant placement for fuses. what you might want to do is read the owners manual or go to vw's website and find out the fuses location then you can replace it

when you take the steering wheel off the is a abs sensor ring (round) if this is damaged the horn will not work cheers

1 take air bag out
2 take bolt of for the steering wheel
3the sensor will be underneath the steering so pull off that aswel as the steering wheel
4replace the rounds plastic ring(the horn also conects to it
cheers

your multi function switch is bad. hope this help buddy