Mercedes-Benz Forum banner

1 - 20 of 48 Posts

·
Registered
ML320 PETROL 1999
Joined
·
19 Posts
Discussion Starter #1
ML320 BLOWING HORN

HI GUYS,CAN SOMEONE PLEASE HELP ME.

MY HORN JUST STARTED BLOWING ON ITS OWN FROM NOWHERE ONE DAY ,IT WOULDN'T SWITCH OFF UNTIL I PUT THE IGNITION KEY TO START POSITION AND OR WHEN I START THE CAR.

THE ONLY WAY I CAN SWITCH IT OFF NOW IF THE KEY IS NOT IN IS TO TAKE OFF THE HORN FUSE.

THE ALARM/IMMOBILISER STILL WORKS FINE. CAN SOMEONE PLEASE HELP.

I'VE HAD MY ML320 FOR 2YEARS NOW WITHOUT ANY PROBLEMS AT ALL.

PLEASE HELP,THANKS GUYS.
 

·
Purple Moderator
99 ML430, 00 ML320, 05 E500 4matic Wagon
Joined
·
22,119 Posts
Please turn you caps lock off on your keyboard.

Is it the third horn near the firewall? That is usually the one that goes off when there are
alarm or tow sensor warnings.
Also we do not know your year. Please finish filling out your User CP so members can give
you more accurate help to troubleshoot problems.
 

·
Registered
ML320 PETROL 1999
Joined
·
19 Posts
Discussion Starter #4
thanks for your reply,my bad for the caps which i have removed.i have also updated my user cp as you said,my ml320 is 1999 petrol with 81 000miles,in uk/britain.

i am not very technical what do you mean by firwall?

from the pcitures you attached the problem horn would be h3 on the left side.

i hope this info will help.
 

·
Registered
ML320 PETROL 1999
Joined
·
19 Posts
Discussion Starter #6
thanks for the great help,but how conclusive is this coz my alarm and immobiliser work fine ,its just the horn that is the problem??

i say its just the horn coz the alarm siren is very different from the horn sound which i hear when i press the bell on the steering wheel.

your diagnostics seem to relate to the alarm system not the horn.
 

·
Premium Member
02 ML320 06 ML500
Joined
·
17,098 Posts
thanks for the great help,but how conclusive is this coz my alarm and immobiliser work fine ,its just the horn that is the problem??

i say its just the horn coz the alarm siren is very different from the horn sound which i hear when i press the bell on the steering wheel.

your diagnostics seem to relate to the alarm system not the horn.
You have already stated the the horn that is sounding is H3 on the firewall. That means that is the alarm horn.
 

·
Registered
ML320 PETROL 1999
Joined
·
19 Posts
Discussion Starter #9
okay thanks,any idea how much this Trip Computer would cost?
Is it possible to disable the tow away sensor before i have the money to replace the Trip computer?
 

·
Premium Member
02 ML320 06 ML500
Joined
·
17,098 Posts
okay thanks,any idea how much this Trip Computer would cost?
Is it possible to disable the tow away sensor before i have the money to replace the Trip computer?
Search ebay for a used ML trip computer.

To disable the alarm system is in your owner's manual.
 

·
Registered
ML320 PETROL 1999
Joined
·
19 Posts
Discussion Starter #11
hello,i've just physically checked out my engine and i didn't see that horn on the left inside which would suggest the horn must be the h2 ones in your attachments.

So any idea how i would solve this horn problem with this new scenario please?

If i disabled the alarm will the horn stop blurring?
 

·
Premium Member
02 ML320 06 ML500
Joined
·
17,098 Posts
hello,i've just physically checked out my engine and i didn't see that horn on the left inside which would suggest the horn must be the h2 ones in your attachments.

So any idea how i would solve this horn problem with this new scenario please?

If i disabled the alarm will the horn stop blurring?
Yes it will but that has to be done every time you lock the vehicle.

You probably have a different alarm system in Europe.
 

·
Purple Moderator
99 ML430, 00 ML320, 05 E500 4matic Wagon
Joined
·
22,119 Posts
You are correct 43, a lot of the EU versions do not have the 3rd horn.

I did not realize that until he posted his location.

I just checked eBay UK and here. There is a reputable seller I have dealt with in Minnesota
that ships to the UK. They have brand new ones.
It is about £90.00 including shipping.
Ebay item #271042738439
 

·
Registered
ML320 PETROL 1999
Joined
·
19 Posts
Discussion Starter #14
thanks i will look in the manual

dont you think a brand new one will be better from ebay?
 

·
Registered
ML320 PETROL 1999
Joined
·
19 Posts
Discussion Starter #16
thanks for that so you think if i buy a new horn relay this might help coz its not the siren sound coming out but the steering wheel horn.
 

·
Premium Member
02 ML320 06 ML500
Joined
·
17,098 Posts
thanks for that so you think if i buy a new horn relay this might help coz its not the siren sound coming out but the steering wheel horn.
K2 is the horn relay. Swap it with K1 which is the rear defroster.

Since your alarm system does not have a separate alarm horn, it uses the regular horns as the alarm horn. So don't believe that it is just a regular horn issue.
 

·
Premium Member
02 ML320 06 ML500
Joined
·
17,098 Posts
Please explain further. The UK ML's have an OE siren module located near the right front wheel liner that is used for the security alarm function. #20 in below EPC diagram. How are the steering wheel horns related to that system?
Mike
Mike, I don't know their system and how it works. He has to.
 

·
Registered
ML320 PETROL 1999
Joined
·
19 Posts
Discussion Starter #19
thanks guys for your great contribution.i just put in a new relay but didn't help.

had to go to local dealer who said first they need to run diagnostic tests which will cost usd 95 plus vat per every 30minutes.they reckon water might have messed up the computer or loose connections behind the steering wheel.they said i would expect a total bill of around usd 1000.wow,i'gutted!

any other cheaper solutions are welcome please.
 

·
Registered
2000 ML430 (Sold)
Joined
·
1,209 Posts
The solution is quite possibly a 90.00 euro overhead trip computer, which 43 and noodles have posted.
You need to find out which horn is sounding. The alarm horn, or the steering wheel horn.
After shutting down the truck, what fuse are you taking out. What is it labelled as?
 
1 - 20 of 48 Posts
Top