Does my 94 e420 have built in led/ switch?
 

My 94 e420 picked up a check engine light the other day after my wife filled it with gas. It runs great, I can't see that there is any drivabilty issue with the code. Does this car have the built in led/switch to check engine codes? Where is it located?

Don't want to take it in if it is something that has already reset.

Thanks

I think it should have it. It will be ahead of the module box near the passenger side hood hinge.

Can anyone provide a pic of this switch?

Ok, found it. I'm gettin a code 19. Looks like maybe an injector short or something related. Is this a sign of the infamous engine harness replacement coming on?

Thanks,
Chad

Look in the archives. code 19 is infamous. It is an adaptation code and has relatively nothing to do with injectors as the code definition states. The code 19 in v8s always means you have ran out of lean correction in the lower partial load range. The car is too rich and the software can only take it so far in correction and when it runs out of room the code is set.

MBs answer is new software housed in a $1800 hardware package. The original software will allow 15% fuel correction lean or rich. If 1.00 is the original calculation the the range of correction is from .85 to 1.15. The new software changes the capabilities to 32% or .68 to 1.32 and solves the problem without finding why the car went rich to start with. The AMM is often the reason the mix is skewed, but the software is eventually the answer. Lots of info here, if you can burn your own chip the 36k file is widely available.

Haven't been on this board in a while.

As the self proclaimed originator of the code #19 fix, I'm glad to see that another individual (it seems) has been helped.

If you have not fixed this yet, do a search for JIMF on this forum. He can get you a chio.