the amp doesnt comeup at all.
no blue light , no display.
i check my schematic u send me earlier for the xti 4000 (138349-12_A) and it seems the same as the xti 2000 amp.
there is a +15 v that drives many ic in the PSU that doesnt come up.
I measure R374 (48.7 K) resistor and it read zero.
i replace it but something keeps the +15v output to zero volt.
now i have to check if there is short circuit that goes to the ic's.
D31 15v zener diode is good.
the +15v drives the bias of the 3 transistors Q39, Q40 and Q 41.
I hope with this info u can help me out DGLASS.