Gasboy 1000 Series FMS Diagnostic Manual - Manual (Page 119)

GASBOY Series 1000
6-34 03/07/03
Can't Exit Self-Test
Possible Cause Checks Corrective Action
Incorrect dip switch setting on
MPU PCB. Examine dip switch settings of
positions 5 through 8. All
positions should be open. Open any dip switch positions
(5 through 8) that are closed.
Press the reset switch on the
MPU PCB after changing
switch positions.
Defective self-test switch. Using a DC voltmeter,
measure between DC ground
and P2 pin 4 of the Printer
Status PCB. +12VDC is
measured when self-test
should be off; 0VDC is
measured when self-test
should be on. Turn self-test
switch from off to on. Does
voltage change? Replace Printer Status PCB if
voltage does not change when
switch position is changed.
Defective switch sense IC on
Auxiliary Communications Port
PCB or defective MPU PCB. Using a DC voltmeter,
measure between DC ground
and U12 pin 4 of the Auxiliary
Communications Port PCB.
+5VDC should be measured
when self-test should be off;
0VDC should be measured
when self-test should be on. Replace the Auxiliary
Communications Port PCB if
0VDC is measured when self-
test should be off.
Replace the MPU PCB if
+5VDC is measured on U12,
pin 4, of the Auxiliary
Communications Port PCB
when self-test should be off
but self-test is still printing.