We Have a 1998 ML320, Recently We've Had Problems with the Key/Ignition System

We have a 1998 ML320, recently we've had problems with the key/ignition system.

Frequently when trying to start the vehicle we could turn the keys, all the way to start and the dash warning lights etc... would light up but no attempt to start at all. Turn the key off and back on and a good crisp start, and away we'd go no problem. This seemed to be progressing with more frequent non-starts. (it is notable that the key/lock would also let the key come out/b pulled out without turning and continue to run fine.)

3 nights ago the car wouldn't start on most key turns (like 9 of 10), and when it did would start and run for 15-30 seconds and stop running. We had the car towed, the facility we went to asked for all of our keys; I took them both of our main "KeyFob Keys" and the valet key. The problems persisted with both main keys, interestingly the valet key started the car and it ran fine!! This facility was not a MB dealership, (though specializes in MB autos) so wasn't authorized/able to make new keys; so we brought the car home tonight using the valet key (and once it too seemed to have had a blank turn/start although it may be user error).

We had both main fob keys replaced at the MB dealership in June of 2009, for similar problems! That mostly solved the turning of the key and not starting at that time. But did slowly get back to probably 1/2 of key turns being "blanks" (so to speak) then to

where we were 3 nights ago.

The Error Codes are:

ME2-SFI - Motor Electronics 2

P0400 EGR: malfunction(function chain) current

P1570 Start enable of DAS not sent current and stored

ETS - Electronic traction system

C1210 Unknown fault code Unknown fault type: -1 stored

AAM - All Activity Module

B1703-004 transponder: error when writing programmable code stored

B1858-002 Two-way radio signal : the programmed code is o.k., stored

but the programmable code is not synchronized.

B1703-000 The transponder cannot be read. stored

B1703-001 The programmed code of the transponder is invalid. Current

and stored

B1703-002 The programmed code of the transponder is o.k., Current and

the programmable code is invalid. stored

ICM - Instrument cluster with maintenance interval display

B1470-001 Componant Fuel level sensor has l- -l -, -//- (sort of the stored

right symbols)

B1471-002 Componant Outside temperature sensor has l- -l -. stored

(again, sort of the right symbols)

Battery Voltage 11.08 V

PPPhhheeeew!!!! probablytoooomuuuuch info, (i have more stuff like MB numbers, HW version, SW version, Diagnosis version, and Pin; for each if it would be helpful) but.... .

Sooo, what does this all amount to? What is the fix? Why and did the two newish keys fail?How should the keys be treated differently??? Any and all thoughts, ANSWERS, and suggestions will be greatly appreciated!!!!

THANKS!!