Hi all,

2005 CLK55 cab with about 94,000.

I am getting an ABS Display defective, Brake Wear Warning, ESP warning visit workshop message and the car goes into limp mode. Any suggestions? Here is the list of things done by me and the dealer so far...

1) Secondary Air pump went. Removed and tested with spare battery...and it was completely seized. Replaced (FCP EURO). Still blew 40 Amp fuse after replacing. Research said when the air pump goes the Front SAM can go to due to circuit overload even with the fuse.
2) Replaced the front SAM (FCP EURO) and put the code on it from the original SAM using LAUNCH.
3) Started getting a simultaneous ABS, ESP, Brake Wear warning with the car going into limp mode. Could rectify by putting car in park, turning car off and restarting. It would happen randomly but once it started it would be more frequent as time went on. Off to dealer to check my SAM code, recode it just in case, and get a Star blessing. Problem came back.
4) Replaced voltage regulator (the one was fine, but I was there).
5) Replaced the battery.
6) Problem still persists. Dealer has swapped back original SAM. Problem still there after driving about 25 miles. Dealer also swapped out the ESP/ABS module thinking it was bad and the problem remains (put old one back on so no charge to me). All their CAN tests come back fine and they have tested for codes while the problem was active.

Dealer is trying to work with me and vise versa but we all are stumped. Has anyone else had this problem? What were your cures? Dealer is just as curious as I am.

I have also replaced the A/C compressor this year (FCP Euro), spark plug wires x16, and one coil that I noticed had a corroded plug wire connected to it. It was the passenger side 3rd cylinder back B plug if memory serves. Other than this, the car has been bullet proof. A while back i did the conductor plate on the trans and plug, fixed a bunch of oil leaks (minus the rear main seal), spark plugs, belts, pulleys, and replaced all the cylinders for the top including a pump rebuild. The only shop work I had done was the A/C compressor, ref sensor, and wheel bearing, otherwise all the work has been done by me.

I am thoroughly stumped on this one.

Thanks for the help!

 

Sounds stupid but did you clean/replace your speed/break sensors with break clean real good? Sometimes they can be very temperamental and it will throw the car in limp mode and give you an ABS/ESP light on the dash. I had a really bad, rusted and broken front wheel speed sensor and once replaced it took all of my problems away. (Same as you, car in limp mode, ABS/ESP Lights on) Mine was in bad shape, however I have heard the same with ones that just have a little corrosion or brake dust build up on them giving people headaches.

Either way good luck

 

[Thanks PhillyCLSJoe. I called the dealer and they told me they did the diagnostic of these while running the car. The sensors checked out fine. They told me they are getting a low voltage signal to the ABS/ESP Module. Any thoughts? The only other thing i can think of is the Brake switch that runs off the brake valve (w209's did away with the brake switch under the dash that w208's had). Thanks for the reply...appreciate this community's willingness to share knowledge.

 

any luck on a fix?

 

TMJCLK55,

I ran more diagnostics last night. I have a spare car to use, but i really want to get back to my 55. It is my daily...snow tires and all.

Ok, here is what I did. I cleared all codes to start virgin. Turned car on. Immediately threw ESP Codes C1130 (speed sensors x2) and C1001 and C1000 (N47-5 ESP and BAS control module are bad). I am using a Launch scan tool. The dealer replaced the N47-5 module to no success (and took it back when it did not fix the issue) This leads me to potentially a bad pump or brushes on the pump or a sensor.

I then tried to force actuate the ESP/BAS system/pump to see if i could at least hear it operating. I discovered one of the parameters is not "in range". Specifically the A7/7b1 BAS Travel Sensor. It had a reading of .19ft or 57.912mm. Max allowed value to run the actuation test is less than 8mm. When pressing the brake it increases in value (as it should). At rest it returns to .19, .15., .14.

I have ordered a new travel sensor from FCP Euro. They do not list the CLK (300,500,55) in their fitment list, but they have the C55 listed. They ran my VIN and confirmed fitment.

I am going to laugh if all of this was over an inexpensive stuck sensor. I'd be a little surprised that STAR did not see the value. Stand by....

 

Standing by.....hope it was the culprit for you.

I first had this same dash light warnings. Turned out my rear brake pads were shot. Not long after I replaced them and inspected my rotors and replaced front rotors and pads with new sensors, I had the same issue again but this time, my speed signal on the speedo cluster would be gone. Car "stuck" in first gear I think. Says to visit workshop. I checked my battery one day and found the old one I had, was low on electrolyte so I topped it off with new battery acid and distilled water I mixed. Charged it then ran it for another 4 years. Same issue started again last year and after replacing the battery with a newer model design, I don't have the issue anymore.
I noticed you mention replacing battery and test conducted on speed sensors and alot other test but all with no success. I hope you really do find the issue with this.

 

I had similar issues that went away with a new clockspring/steering angle sensor.

 

If you do a search, there have been many people who get an ABS malfunction light and the replacement of the brake light switch at the brake pedal ($20 dealership) has solved a bunch of these problems...don't ask why but thought that you might try it for small money.

 

Update...

No joy. I also tried the one connected to the brake booster b/c i was getting odd readings on my scan tool from this sensor. Also no joy. I had the opportunity to sell it (while it was not throwing consistent codes) and in good conscience i could not do that to an unsuspecting person.

After four months it was tossing codes consistently so i decided to sell it at auction through a car dealer knowing a buyer was getting a known issue(s) and the car was fully disclosed. It is almost as if it has wet or corroded wiring somewhere. All the same, after losing weekends wrenching/diagnosing/probing i had had enough. I went to the bank to get the Title and on the way out the door a gentleman asked if it was my Mercedes out front. I said indeed to which he replied "beautiful car". One last knife in the heart i suppose. Ironically, it let me drive almost 6 miles to the dealer without going into limp mode save the last 500 feet.

I replaced it with a 2014 E550 Cab so i can stay in the same chassis ecosystem and do a project i've been thinking about. CLK issues aside, i love these cars.