IBM 3112, Service Manual

Page: 43 / 184

bh1s.bk : bh1sdiag.doc 27 Thu Apr 20 12:42:16 1995
Diagnostic Information
27
If the printer beeps 5 times at POR, or if the operator panel is blank:
check for +5VDC at pin 4 of the cable connector at the operator panel,
and also at engine board J1-4. Replace the operator panel or the cable
if they are the problem. If the voltage at the engine system board is
incorrect, check that the LVPS is pro5VDC at J4-7, J4-9, and
J4-11, and replace the LVPS if its output voltages are wrong.
Paper Feed Problem, 500-Sheet Second Tray
Remove the module and inspect the tray, the module D-roll and the
gear train. Make sure the gear train is meshing with the drive gear at
the bottom of the printer. Look for other mechanical problems or dam-
age. Make sure the printer and module auto-connectors mate properly
when the module is installed.
If the paper is not being picked, run the Print Test with the RIP Board
removed. Check for +34VDC at engine board J15-2. You can test the
torquer motor by shorting engine board J15-1 to ground (J15-3).
Paper Feed, Base Printer
Run the print test or the diagnostic paper feed test and carefully exam-
ine the area of the problem.
If paper is not feeding, make sure the paper is in the tray correctly and
is not damaged or stuck together. With 500-sheet trays, make sure the
tension wheel is set high enough to give good contact between the D-
roll and the paper stack.
If paper is not feeding or is feeding continuously with no gaps between
pages, remove the paper tray and the RIP board. Press switches 1 and
3 on the paper size switch assembly. Watch the D-roll as you run the
Print Test with RIP Board removed. One of the following will occur:
•
The D-roll will make one complete revolution and stop with the
flat side down. This indicates that the paper feed magnet and
gear train are working correctly.
•
The D-roll will turn continuously. There is a possible short to
ground of the leads between the paper feed magnet and engine
board. Examine the condition of the paper feed magnet leads,
and replace the magnet if necessary. If no problem is found,
replace the engine board.