So both onboard supplies are running on the low side.

The SMPSU chip is powered by the 5v rail, so if this is low the calibration will
be completely off.

As a further test, measure the voltage at TP37 (next to the inductor on the back
of the PCB). This should be around 14-15v, as it is the DC input line direct from the input jack via a diode or two.

Check pin 2 of PL2 ( second from the left, looking at the PCB from the back). This
should be 5v.

All the pins on the side of the resistor pack nearest the center of the display board
are connected to 5v. Check this voltage as well, it should be 5v.

If it isn't, unplug the display board, turn the empeg on, and check the voltage on pin
16 of the display connector (third from the left end, bottom row, looking from the
front of the empeg). This is the main 5v rail to the display board. Also check pin 14
(next pin on the right) for 3v, and either pin 19 or 20 (left end of the connector) for
the DC IN voltage of around 14v. If any of these voltages measure 0v, one of the
main fuses has blown.

Assuming the 5v supply from the empeg main board is present, measure the
resistance from pin 16 of the ribbon cable to any pin on the center-pcb side of the
resistor pack. This should be near enough 0 ohms. If it isn't, the likelyhood is a
burned out or damaged track.

Also, what value resistor pack has been fitted? It should be 1K. If it is
considerably lower than this, it is possible that the IR PIC could be damaged due
to overcurrent, which would kill the dimmer, the IR recieve, and the switches.

Pca