'95 and later, the procedures is a little different:

1) Set left wheel to red detent (HI) and right wheel to blue detent (LO);
2) Turn ON ignition;
3) Press AUTO (displays show HI/LO);
4) Within 20secs simultaneously press REST and EC buttons for more than 5 sec.
5) The LED in the RECIRCULATE button flashes and "OFF" appears in the display.
6) Press the right 'AUTO' button until all DTCs are displayed and recorded.
7) To erase all, codes must be read out. Press both 'AUTO' buttons simultaneously for more than 5 secs. "d" will be displayed on the left and "FF" is displayed on the right.

Try that out and let us know.

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Regards . . . . JimF
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'94 S500 Cpe

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