BMW Repair Questions? Ask a Mechanic for Answers ASAP
Hi, How are you?I'm Shabaz, one of the automotive experts, I'm sorry you're experiencing problems with your car, I will do my best to help you today.
Have you tried taking the car to an independant garage for a second opinion? £700 is normal for BMW, not really surprised.
Since I received no response, I will leave you with a general answer and I hope this helps.
To diagnose this issue, (assuming that the fuse has been checked) the wiring at the horn needs to be tested with a multimeter set to DCv and then get a second person to press the horn and see if you are getting power when the horn is pressed. If there is no voltage, you will need to access the wiring to the horn switch (it will have 2 wires) and you should have 12v on one of the wires. If there is power on one wire, there is a problem with the horn switch or clock spring. The clock spring allows the steering to turn freely whilst maintaining an electrical connection to the various switches and controls on the steering
These parts are available to buy used on ebay and you can then use an independant BMW specialist to fit these parts which will cost you a fraction of the £700 BMW are charging.
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