Marsh 4BT Manuel D'utilisation page 32

Troubleshooting
Do not attempt to repair anything other than a broken wire or connection.
Problem: The machine will not operate when any button is pushed.
Possible Cause:
1. The machine is not plugged in or turned on.
2. The machine will not operate when any button is
pressed.
3. The computer board is defective.
4. There is a problem with the wiring in the power
transformer or with the power transformer itself.
5. There is a problem with the logic board assembly,
the switch finger plate or the connector plug.
Problem: The machine is producing inaccurate lengths of tape or it does not shut off
after touching a button has started the machine.
Possible Cause:
1. The computer board, the diode logic board, the
pulse switch, or the magnet may need to be
replaced.
25005/97231 Rev D
Solution:
1. Be sure the machine is receiving power from an
electrical outlet and the power switch is turned on.
2. Plug in the machine and turn the power on. Press
one of the buttons and if the machine does not
operate, remove the left cover plate to expose the
wiring. Connect a jumper wire between an orange
and a blue lead. This should cause the machine to
run continuously. The basic unit is not defective if
the machine is running.
3. Replace the computer board. See page 63 for details.
4. If replacing the computer board does not activate
the machine, the measuring head must be replaced.
See page 65.
5. The logic board assembly must be replaced. See
page 69.
Solution:
1. Replace the computer board following the steps on
page 63. If this does not solve the problem, replace
the logic board assembly following the instructions
on page 69. If neither of these solutions work,
replace the measuring head, which includes the
pulse switch and magnet. See page 65.
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