I know this has been discussed a few times but I have a bit different twist on this light...I think.

The "CEL" comes on, nothing seems to change, the car (1990 300E) runs fine. I get home, disconnect the battery for five minutes or so, the light is off.....for a couple hundred miles or so.

What would be the reason for this? Should I change the oxygen sensor?

As always your input and knowledge is greatly appreciated!

TIA
Michael

 

might be the O2 Sensor, but you can check it by holding the button down and counting the flashing lights...

 

Whoa Jorge.....what button, what light?? Where is it?? This is a 1990 300E, does it have this....I see you have a 1992.

TIA
Michael

 

well it's this little box that's next to your battery...it's the 16 pin data link connector. It allows you to plug in the diagnostic code reader and let's you see whats wrong with the car, through a series of flashes...It's covered with a little cap.

 

california version got it.

 

Jorge & SW...Thank you guy sooo much!

I started the engine, pressed the button on the data link connector, the led blinks 11 times and does not repeat the blinks. Does that tell anything or do I need to get a reader? The car is a 1990 300E, which reader do I need? I have been looking on the web and find OBD1 & OBD2 readers as well as both designations in one reader.

The family cars include a few 1996 and newer cars too....whiich reader is the one for me?

This forum is theee best thing since......fuel injection! Thanks again guys!

TIA

Michael

 

lol...I found this step-by-step page I was looking for earlier..kinda useless now but what the hell.

Reading Fault Codes

- Turn ignition key to โ€œonโ€ position, all dash warning lights will be on.

- Remove cover on 16 plug diagnostic connector near battery.

- To read check engine light codes (DM), hold down built in button next to LED light for 3 to 4 seconds, LED light should be on, release button, count the number of LED flashes that follows. Hold button down for 3 to 4 seconds again to check for another code. Keep doing this until all codes have been read and first code comes up again.

- To clear codes - hold down button for 10 to 12 seconds, turn ignition key off for a few seconds, repeat to clear additional codes. Ignition must be turned off between each code cleared.

To check other modules using code tester โ€“ insert black plug into socket #1 (ground). Insert red plug into socket #16 (12V power). Insert yellow (third color) plug into socket to be tested, for example #8 or #14. Repeat steps above for LED button using code tester button and LED. Same process for deleting codes as with LED button.

Check appropriate fault code list to determine fault.

Checks codes as quickly as possible at the first sign of a problem. Codes spread from one module to another and will often show up twice or cause other codes. The sooner you check the codes the more likely you are to identify the source problem.

Ok. Since I think your car has the m103 motor, I found a list of error codes that you can base those 11 flashes on, download: http://www.yousendit.com/transfer.ph...271D60738B97A2

Here's the link (DIY) on how to build your own code reader: http://www.yousendit.com/transfer.ph...33D09C1C84F28F
Or you can buy the reader: http://cgi.ebay.com/ebaymotors/Merce...11667485QQrdZ1

Good Luck buddy!

 

BC &/or SW,

Lots of info sent! #11 is "air injection"....gee my book does not even aknowledge anything with regard to air injection. I have Bently Publishers Mercedes owners bible. Can you recommend a more thorough book on the 300E?

Your help on this is greatly appreciated!

Michael

 

Well since I don't know much about that code myself, a friend of mine helped me out:

"Air injection is an emissions process carried out by a pump that is usually driven by the fan belt.

Your car should have an air pump. Code 11 is telling you to look at air injection. My first shot would be to look in Section 14-7165 of the manual. It may provide some information."

 

BC, Ahh..."smog pump" hummm. Is this the factory manual you are talking about? Where would I get one? I'll look around on line, there are a lot of junk manuals out there....I have a few! Don't need any more. I got a transmission one that is so sad.

Thanks again!

Michael