Problem with Alt 2

Hello everybody I have a cirrus G1 SR 22 with a alt2 problem. The alt2 yellow light staying on so I check the voltage at the alternator 2 field wire and there was no voltage. Then I open the master control unit and one of the gray relay was trip out, I reset it and then I was getting 24v on the flied circuit wire J1 at the alternator now. So we put back everything together and started the aircraft and it went out shortly after. As any experienced this problem?

Well…the header connector on MCU circuit board may be damaged…

Do you know if the #2 batteries are good?

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The J111connector (A) which is the first one for the field circuit for alt2 was damaged form overheating, the terminal was cleaned up with sandpaper and contractor cleaner also the number battery was change 18 months ago.

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And often the bolster switch for alt 2 is intermittent.

Certainly cleaning the field connector and alternator terminals for the field should be considered.

We did tool apart the switch assembly an check it also but the issue remains the same, I was thinking about replacing the alternator or sending out for overhaul

Might be best to replace the alt. I had my control board, alt 1 and alt 2 all burn out in flight. Replaced everything. Now on occasion the new alt 2 will over amp and the warning light will come on.?

I was having issues with Alt1 & Alt2 annunciating intermittently. Per Cirrus, we changed 2 current sensors. Alt1 is now fixed. Alt2 is still on but is supposed to turn off above 1700 rpms.

Have you verified it (ALT 2) is actually producing Power?

You need to insure with the ALT 2 Switch on that E. Buss Voltage is Higher than M. Buss Voltage above 2000 RPM.

If it is not, then ALT 2 is not working, and its not an instrumentation problem.