Fault Control Unit

[begeta50]

I have a 1995 525i, and I have check engine light on. The mechanic conected the computer, and it gave me an error code 200 FAULT DMA. The mechanic says that needs new control unit.
My question is. Can the control unit be fix without replacing it. The unit is very expensive.
The car run great, but I need to pass smog check, and with the check engine light on. it will not pass. I need help.
Thanks

[BillionPa]

since its still driving, i would do diagnostics to identify if a component in the ignition system is to blame for damaging the DME