The suppply voltage is 12VDC on the two outer pins. Applying power
results in a display of "U001" after about three seconds. This I read in an
IBM document, indicates the initialization/self test was successful and the
display is waiting for communications.
U001
Explanation: The point-of-sale display has completed POST is waiting to receive communications from the system unit.
User Response: Wait a maximum of 30 seconds for the next message to display. If U001 remains on the display:
1 Switch Ready mode OFF then press the RESET switch on the operator panel.
2 Switch Ready mode ON and wait 15 seconds.
3 Look at the operator panel indicators.
Ÿ If System Board OK (indicator 1) is off, go to “4693 Operator Panel Indicators and Switches”
on page 1-51.
Ÿ If System Board OK (indicator 1) is on, go to “MAP 0110: Input/Output (I/O) Device
Isolation” on page 1-6.