ECU interchangeable?
 

Is the OEM 1994 C280 ECU interchangeable with the OEM 96 C280 ECU. What are the differences? They do have different part #'s.

Well, apart from a knowledgeable answer from a Mercedes mechanic, I would say this. Do they have the same number of pins in the electrical connector, are the connectors identical and is the color code of the wiring identical. If that is all the same your chances are better, but I think you would have to install it to know for sure.

Whats the part number for the ECU's?

Part #'s are different. I wrote them down somewhere. Pins are identical. Plugs in fine, however, I'm wondering if there are any possibility of frying anything. Different things between the years (mostly A/C control unit items) raise my concern. In the same area of the engine ECU, I notice there is no ABS control unit in the 96.

I'm asking all this because I have a OBDII readiness monitor issue where 3 are not resetting. Will changing out the ECU fix this? My independent suggested this the idea being the ECU is "stuck" on these readiness monitors. I did plug in the 94 ECU into the 96, however, it still shows the same readiness monitors not set when I turn the key to "on" but not starting the engine. Are OBDII items (esp readiness monitors) even related to the engine ECU?

The EPC lists the following part numbers applicable to your C280:

http://i.imgur.com/TjQc8.png

I don't think there was OBDII in 94 so that could be an issue. Have you explored the usual readiness issues?

The 1996 & later fuel computers are "married" to the serial number of the car they were originally installed.

SO no, not interchangeable.