Brake lights staying on my 2005 C230
#1
Brake lights staying on my 2005 C230
My brake lights are staying on all the time any suggestions on what it could be? according to dealer there is no brake light switch on the brake pedal.
#2
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2007 C230 and 1985 Monte SS
I find that a bit hard to believe... try looking under there yourself. There has to be a switch somewhere for the lights, cruise control disable, BAS, etc.
On my older car, the brake light switch will sometimes come out of algnment with the pedal and keep the lights on.
On my older car, the brake light switch will sometimes come out of algnment with the pedal and keep the lights on.
#3
Super Moderator
This is an interesting one. My previous Benz had a pressure switch in the system -
(i.e. when pressure came up in the system under braking it turned on the lights) - nothing on the pedal. I suspect that the pressure switch is probably now integral with the ABS but it might still be separate. Sorry I can't answer this one definitively but tell the dealer to wake up - I'm pretty certain that there is a pressure switch somewhere.
(i.e. when pressure came up in the system under braking it turned on the lights) - nothing on the pedal. I suspect that the pressure switch is probably now integral with the ABS but it might still be separate. Sorry I can't answer this one definitively but tell the dealer to wake up - I'm pretty certain that there is a pressure switch somewhere.
#4
MBWorld Fanatic!
Yeah - This one made me laugh...the dealer says no switch on pedal...is that the extent of their knowledge...How do you trust some one to work on / fix your car if they don't know how the stop lamps turn on?
MMMMMMM...
Jake
MMMMMMM...
Jake
#5
Super Moderator
Brake light activation pre & post facelift
OK - Some research & we have the answer - There might be some discrepency from market to market as to when this was instituted but this is the best data I can establish regarding US cars.
Brake Light Activation
Pre facelift
The brake light switch is on the pedal bracket up high above the brake pedal, there is a little offset to it but it strikes the pedal itself. 2 connectors on the US versions,
Post facelift
Electronic Stability System (ESP)
• Private-Bus (CAN)
– CAN between ESP and micromechanical turn rate sensor
(B25/15)
– 2-wire CAN used to transmit rotational speed and lateral
acceleration data to ESP
• Brake light control
– Brake switch eliminated
– Release contact of BAS system used to determine brake
application
(brake pressure & membrane travel used as back up)
– Redundant signals
• Discrete wired from ESPàSAM-D (looped)àSAM-R
• CAN signal ESPàEISàSAM-R
• SAM-R confirmation reply via CAN
– Brake light suppression via CAN message from ESP
This is extracted from a huge, DB pdf. file that I can no ways attach here. See highlighted under Brake Light Control
Please take this to your jerk dealer to assist him with fixing the problem - Good luck This is not a DIY
Brake Light Activation
Pre facelift
The brake light switch is on the pedal bracket up high above the brake pedal, there is a little offset to it but it strikes the pedal itself. 2 connectors on the US versions,
Post facelift
Electronic Stability System (ESP)
• Private-Bus (CAN)
– CAN between ESP and micromechanical turn rate sensor
(B25/15)
– 2-wire CAN used to transmit rotational speed and lateral
acceleration data to ESP
• Brake light control
– Brake switch eliminated
– Release contact of BAS system used to determine brake
application
(brake pressure & membrane travel used as back up)
– Redundant signals
• Discrete wired from ESPàSAM-D (looped)àSAM-R
• CAN signal ESPàEISàSAM-R
• SAM-R confirmation reply via CAN
– Brake light suppression via CAN message from ESP
This is extracted from a huge, DB pdf. file that I can no ways attach here. See highlighted under Brake Light Control
Please take this to your jerk dealer to assist him with fixing the problem - Good luck This is not a DIY
Last edited by Glyn M Ruck; 02-13-2009 at 04:01 PM.
#6
thanks for your help, I have been under the dash all day and I really don't think there is a swith on the pedal, but I do feel that there is a pressure switch, although when I disconnect them (there are 2)the lights stay on, when I disconnected the ESP control the lights went out, is it possible that it is something else, since that part is 900 bucks!
#7
Super Moderator
You have a 2005 - it's not on the pedal. It's activated by the Brake Assist (BAS). Keep us informed. I'll try & do some homework on the brake assist. Must go to bed 4am in the morning this end
Last edited by Glyn M Ruck; 02-13-2009 at 09:50 PM.
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#10
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06 C230 SS 6spd
sometimes its the contacts in the socket of the holder. if you remove your bulb and look at the contacts inside, sometimes theyve been know to overheat and fuse together causing a constant in the brake light or the light not working anymore. you can sometimes fix it by removing the melted parts, of course with the harness disconnected. if its too damaged you'll need a new one.
#11
sometimes its the contacts in the socket of the holder. if you remove your bulb and look at the contacts inside, sometimes theyve been know to overheat and fuse together causing a constant in the brake light or the light not working anymore. you can sometimes fix it by removing the melted parts, of course with the harness disconnected. if its too damaged you'll need a new one.
#12
Junior Member
I'm having this problem with my 2000 C230. The "Brake Pads Worn Down" light is on and all three brake lights stay on all the time. The two must be related, but how?