[Duke of Ale]

I have a C 240 4 Matic and need to put a new sensor in. Does it need to be relearned and can it be done without a scanner? If I do this at home, will it start again? I will buy a scanner that will do the job at home if I can find one for less than $300. U.S.

 

[rudeney]

It is not necessary to relearn the CPS. It will work without coding.

 

[Benzyle]

Rudeney is correct as usual ,,,,however it is also good practice to do a Crank shaft position sensor flywheel adaptation immediately after fitting a new CPS.
Allow engine to warm up to at least 70 degrees,,Trans in Park,,slowly build up rpm to 2500,,,then
Run at 2500 rpm for 30 seconds ..then drive the car..

 

[Duke of Ale]

Thank you. The reason I ask is in my Haynes Repair Manual on this car, there is a statement regarding V-6 models that the new unit must be re-initialized by a STAR DIAGNOSIS unit. However, a search on the internet did not come up with any mention of that. There is even a YouTube video on replacing that sensor in the same car I have and there was no mention of re-initializing it.

 

[RedGray]

Buy one directly from an MB Dealer. Then, the difference between sensors will be minor. And, the new sensor will be learned/adapted-to quickly.
Just do not go around red-lining the engine until after ~~300+ miles or normal driving.

Fwiw, the same is true for GM vehicles.
Many people just replace the Crank Sensor with an AC-Delco new sensor, and then go on to live their lives.
I have a GM TECH-II scanner. So, I can do it from the scanner.

Good Luck!

 

[Planethill]

Buy one directly from an MB Dealer. Then, the difference between sensors will be minor.

Or just buy a Bosch sensor for 1/2 the MB dealer price. It will be the exact same sensor.

 

[260e crusier]

I've changed four CPS (four different cars) so far and it's been "plug and play" for me with no issues.

I heard you're suppose to do a flywheel adaptation though. I tried it one time and didn't notice any difference. Post #8 here:

Engine randomly dies - CPS adaptation

My wife's E430 has died twice randomly while driving. She says it just quits running. No engine codes, car starts back up and runs fine. Could it be a low battery in the key? (I had her change it last night just to be sure) Any other suggestions?

www.benzworld.org

 

[rudeney]

Buy from a reputable parts specialist - just don't buy from eBay or Amazon as they are full of fakes.