SL/R230: All buttons on steering wheel sound (honk) horn...
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Joined: Aug 2020
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From: Gretna, NE
'03 SL55 Black, '03 SL500's Aegean, Mars Red, Tazanite, Alabaster, '11 S550 Flint Gray
That's a new one. The buttons are really small modules that transmit data over the clock spring. This allows you to have all of the switches on the wheel without an extremely complex rotary connection. The right side is the master that is actually connected to the clock spring. The left side transmits data to the right side switch module. The data is read by the steering column module and distributed to other modules over CAN. My first guess would be a problem with the clock spring since it is the moving part and likely the most prone to failure. After that, I would suspect the right side switch and then the steering column module. The clock spring is three conductors: power, ground, data. There are actually two clock springs, one for the switches and one for the airbag ignitors (steering wheel bag has two ignitors).
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SL500
That's a new one. The buttons are really small modules that transmit data over the clock spring. This allows you to have all of the switches on the wheel without an extremely complex rotary connection. The right side is the master that is actually connected to the clock spring. The left side transmits data to the right side switch module. The data is read by the steering column module and distributed to other modules over CAN. My first guess would be a problem with the clock spring since it is the moving part and likely the most prone to failure. After that, I would suspect the right side switch and then the steering column module. The clock spring is three conductors: power, ground, data. There are actually two clock springs, one for the switches and one for the airbag ignitors (steering wheel bag has two ignitors).
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From: Netherlands
2005 R 230 SL350 (M112 3.7). Sold the 1966 W113 230SL recently
Don't know what breezing over means here, but aren't your buttons dead and aren't you just pushing them so hard that you're actually pushing the 'big' pad that is supposed to activate the horn?
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SL500
'Fraid not. Breezing over implying not mashing them. Typical gentle press = "honk". All 4 buttons.
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SL55 AMG
I’ve had this issue on two different SL55’s and from memory give you the fix that worked for me. I did a quick search and cannot find this again but here goes from memory. My friend’s SL55 got so bad the horn would come on permanently until the fuse was pulled.
Disconnect the Consumer battery
There’s 2 screws on the back of the steering wheel to remove the airbag. Seems like they were star screws but can’t really remember.
Pull off cover and carefully disconnect airbag wires ( I’m sure you can find a better description / video how to do this).
There’s 4 springs at the ‘corners’ that are likely collapsed that they allow constant or intermittent contact of the horn with little or no pressure. With your hands elongate / stretch the springs.
Put everything back together.
I did this about 5 years ago and it’s been fine ever since. Let us know if this works for you as well.
Disconnect the Consumer battery
There’s 2 screws on the back of the steering wheel to remove the airbag. Seems like they were star screws but can’t really remember.
Pull off cover and carefully disconnect airbag wires ( I’m sure you can find a better description / video how to do this).
There’s 4 springs at the ‘corners’ that are likely collapsed that they allow constant or intermittent contact of the horn with little or no pressure. With your hands elongate / stretch the springs.
Put everything back together.
I did this about 5 years ago and it’s been fine ever since. Let us know if this works for you as well.
Last edited by Wings55; Dec 5, 2023 at 07:38 PM.
Thread Starter
Junior Member
Joined: Sep 2023
Posts: 22
Likes: 2
SL500
I’ve had this issue on two different SL55’s and from memory give you the fix that worked for me. I did a quick search and cannot find this again but here goes from memory. My friend’s SL55 got so bad the horn would come on permanently until the fuse was pulled.
Disconnect the Consumer battery
There’s 2 screws on the back of the steering wheel to remove the airbag. Seems like they were star screws but can’t really remember.
Pull off cover and carefully disconnect airbag wires ( I’m sure you can find a better description / video how to do this).
There’s 4 springs at the ‘corners’ that are likely collapsed that they allow constant or intermittent contact of the horn with little or no pressure. With your hands elongate / stretch the springs.
Put everything back together.
I did this about 5 years ago and it’s been fine ever since. Let us know if this works for you as well.
Disconnect the Consumer battery
There’s 2 screws on the back of the steering wheel to remove the airbag. Seems like they were star screws but can’t really remember.
Pull off cover and carefully disconnect airbag wires ( I’m sure you can find a better description / video how to do this).
There’s 4 springs at the ‘corners’ that are likely collapsed that they allow constant or intermittent contact of the horn with little or no pressure. With your hands elongate / stretch the springs.
Put everything back together.
I did this about 5 years ago and it’s been fine ever since. Let us know if this works for you as well.
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kia picanto
The wire runs inside the controlling center and down the segment. Some place in there it has scratched against the metal enough to wear the protection off the wire. I would wager cash that in the event that you pull the haggle (need a guiding wheel puller and the right estimated ring nut attachment to get the center point off) you will effectively find the spot that is worn. I'm certain it's up close to the top where the wire moves a great deal when you steer. You could likewise begin by again pulling the horn button and afterward pull a touch of the wire up through the hole in the wheel to check whether it's simply an inch or two down. you should have the option to get another inch or so of wire up into the horn region to investigate, then, at that point, push it back down.
snaptube vidmate
snaptube vidmate
Last edited by sdhayuj; Dec 23, 2023 at 02:37 PM.
