TESTING CONTROL
BOARD
A 1
Confirm that control board A 1 is faulty before re-
placing
it. Use a DC voltmeter and an ohmmeter to
perform the following tests.
1. Disconnect the negative (-) battery cable.
2. Remove the control box cover (Figures
7-1
and 7 -5) and separate it from control board A 1
by removing the four screws on the back of the
board.
3. With an ohmmeter, check for electrical conti-
nuity across each
P1/J1
and P3/J3 connector
on
the
control board (Figures 7-2 and 7 -6). Re-
place the socket portion
of
each connector that
has a measurable resistance (greater than
zero ohms)
or
has begun to corrode.
4. Reconnect the battery and try to start and run
the set.
5. If the engine does not crank, measure voltage
at connector P1-2 while pressing the panel
start switch (the negative (-) test probe of the
voltmeter should be grounded at connector
7-20
P1-8). If the voltmeter indicates zero volts, re-
place control board A 1. If the voltmeter indi-
cates at least
9 volts, the problem is not with
the control board. Go back to the
Trouble-
shooting Guide.
6. If the engine cranks, but does not start, meas-
ure voltage at connectors P3-3 and P3-6 while
the engine is cranking {the negative
(-)
test
probe
of
the voltmeter should be grounded at
connector P1-8). Replace control board
A 1
if
the voltmeter indicates zero volts at either con-
nector. If the voltmeter indicates at least
9 volts
at both connectors, the problem is not with the
control board. Go back to the
Troubleshooting
Guide.
7. If
the
engine starts, but stops when the Start
switch is released, the problem could be with
the low oil pressure switch or generator (no
voltage). Go back to the
Troubleshooting
Guide.
Replace control board A 1 if the oil pres-
sure switch and generator are functioning
properly.
8. Reassemble the control board and cover.
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