Original post updated with fix.  It was a failing PSU.
OK so basically 2 weeks ago we started noticing that our 1900 would have some trouble booting from a cold boot.  It would take longer than usual and occasionally just sit there like it didn't want to turn on but eventually would. Last friday it would't power on giving us Error code E171F (which I believe is related to the PCI Raid card) and CPU 1 error code E1410. We replaced the card and the server powered on and stayed on for a while (maybe 30 minutes or so) but then just turned off. Now it will not power on at all.  The fans twitch a bit like they're about to turn on but then nothing. The power LED is green, PSU LED is green, the only code on the LCD panel is for the intrusion alarm, etc.   Does anyone have any idea what could be causing this?  Would a bad PSU not have some sort of LED indicator as such?  Could it be the motherboard itself?  I'm not really sure what is going on at this point. Thanks for any info or suggestions.  EDIT: The rear LED is not green like I thought.  It's flashing solid amber on/off.   EDIT #2: Holding down the system identification button for 5 seconds produces an "E7" message on the front LCD.   FIXED!  It was the PSU as I suspected.  I presume the PSU was in a fail safe mode not allowing it to power on the system as something internally most likely had failed.  We swapped in a new one and it fired right up.
Power Edge 1900 doesn't power on. Fans twitch and then nothing.