hi, am new hope this topic hasnt been touched on already but is there a reset button or way to turn this light off?
denny

First of all, you should have the code read. It's on for a reason and it might be important.

Secondly, to answer your question, you can disconnect the battery for about 10 minutes and that will do it.

Check Engine Light
 

Battery may be a BAD idea if there's a pushbutton/LED combo switch under the hood. Yes, it will reset the DTC but it also resets the radio codes in my C140. Don't know about W202s.

I personally have not looked at the 202 to know but if there is one check my page (red house) for what to do. Menu item #5 is the Diag Module.

Yes, you should see what the code is before resetting it.

Jim,
202's do not have this.
So that is the only way w/o a scanner!

Hi: You should refer to your car as either a W202 or a C-class, not a W202 class, this is mixing sales designations with chassis number and is considered bad cricket. Anything the last 10 years or so has a non-volatile memory, removing the battery for a few minutes, hours, weeks, months, ain't gonna matter, the code is there to stay until cleared, this is a little more sophisticated than a 1982 Chevy Citation.....Gilly

Yup!!!

The C-class/W202 Chassis will not "forget" codes no matter how long you remove the battery, nor is there a reset button... except with the diagnostic computer at the dealers... :) Basically, you stuck with that code until you bring it to the dealers.
This is what two independent techs told me... Plus, I tried the "removing the battery" bit.... didnt work...

Well I will tell you from personal experience that it cleared my codes.
Well for a day or two, then the car misfired when idling real bad, and it came back on.

So then what is going on?

david....

Maybe you got a special car!!!!! :) hehehhe...

I have been told many times that the 202 computer cannot be reset until scanned by the dealer or whatever....

But... I have been told that if the problem resolves itself ie. temporary sensor glitch.... the code will go away by itself after a while of operation. THAT happened to me. Had the check engine light come on...setup an appointment to have it checked the next week... by that time, the light shutoff... but by next month it was back on again... some sensor had some gremlins in it. :) but all they did was reset the computer and clear the code... and it never came back again...

Yeah, maybe i should restate this. On OBD II cars, the OBDII codes are not supposed to clear themselves ever. If the problem is non OBDII, that is not a code the US Gov't says has to appear, also called a proprietary cade, then it CAN go away after awhile, but it doesn't have to. Up to MB then. OBDII codes are the ones that start "PO", other codes start P1 or PI (one of the 2), this is for engines (powertrain, thanks feds). The OBDII codes are the ones the feds say a manufacturer has to have available for scanning by every shop, I am not sure how they know the independents will have a scanner capable of retreiving it. The proprietary codes the manufacturers don't have to supply any of the scanner manufacturers any info about, just the OBDII codes, although some manufacturers end up with alot of proprietary info anyways........Gilly

hei... thanks for the info gilly!!! :) I learn something new everyday!

Tnx Gilly!
 

My '94 S500, the DTCs will 'erase' if you pull the module out of the F23 box or reset them with X11/21s1 (pb/LED).

Never tried David's 'favorite', disconnecting the battery. If pulling the module erases all codes, then so will disconnecting the battery for my car. And it looks like it will for most pre '96 models. I know that some C class cars had OBDII on board before '96.

Here's an OBDII link: http://www.obdii.com/obdii.html

Always learn something with your posts. Tnx for OBDII info. My car is not OBDII compliant, thank God!