300M engine check light

That code means "No I/P Cluster CCD/J1850 Messages Received"

You can reset the CEL by disconnecting battery power. You can do that by disconnecting the main vehicle ground at the negative jump post on the passenger side strut tower (takes a 15 mm wrench) for 15 minutes. Easier than getting to the battery.

Also - most auto parts store chains will loan you a code reader to read your codes and reset them.

Some codes will also display in the odemeter by doing what is called the key dance: Turn the key to 'Run', then to 'Off' ('Off' being the position between 'Run' and the fully off position in which you can pull the key out) - repeat a total of three times ending up in 'Run' - codes will display in the odometer window.

Quicker still is to pull the computer-related fuses from the under-hood fuse box. On our '02 300M there are two such fuses (10A, I think) in a group of 4 (plus two -- IIRC -- empty sockets) at one end of the fuse box in their own sub-compartment and leave them out for 10 to 15 minutes.

It may be that only one of the fuses needs to be pulled, but I always pull both.

Perce

You are correct. But it's hard to tell someone where the particular fuses are. They are designated as Fuse N and Fuse W - pulling either one will reset the PCM, but I'm not sure they are even labeled by letter in the PDC itself - have to look in the FSM.

BTW - that Fuse W does not exist prior to '02 MY of the 300M, which is another reason I avoid the fuses when telling someone how to reset the PCM codes.

Fuse W is in that group of 5 fuse slots at one end of the PDC - it is the one in the center position. It's difficult to point out Fuse N without a diagram, which I always have handy to post in web-based forums for when this subject comes up. But only one of those needs to be pulled to reset the PCM - so might as well be Fuse W - or remove the power at the neg. jump post.

Oh - wait - I can give you the URL for the diagram showing fuse locations that I keep handy:

THX for all your replies. Interesting that the code description you give Bill is different than on the code description sheet they printed from the Internet. Your desc seems more reasonable.

I've now been on a trip of about 1,400 miles and no return of the engine light. I found a note in my owners manual that a steady engine light may go off after about 5 starts. It says there is no immediate concern if the engine lamp is steady, but if flashing shut down immediately.

Now I'm wondering why this lamp came on with a simple oil change. Did they start the car without replacing something?

The key dance doesn't seem to work on this car. It did on my '95 Concorde so I tried it.

The code description I gave was copied right out of the FSM. People often have trouble getting the key dance to work. I don't know if that feature was removed in later production years - I don't recall that being stated by anyone who knows for sure on the various LH car forums. I have seen discussions in which it was discussed/argued whether the driver's door has to be open or closed, or you have to hold your left foot up in the air, etc. Often after it is discussed for a while, the person who started the discussion because they couldn't get it to work reports back that they tried again and it worked, often with no mention if they determined that they weren't doing it right or not.

Make sure you are using the correct positions of the ignition switch ('Off' - meaning steering wheel unlock, and 'Run').