Control Board Malfunction - Graco GMAX 3400 Operation

Troubleshooting

Control Board Malfunction

Troubleshooting Procedure
(see following page for actual steps):
Remove control box cover. Turn
sprayer ON. Observe control board
Green and Red LED lights.
No light
Once Normal operation
Red light on Control board
continuously commanding
pump to run
Green light on WatchDog
continuously enabled
Flashing See error code
section for further
troubleshooting
Red light on Model not
continuously with selected
potentiometer
OFF after a
replacement
board is installed
Go to step 4.
Is 1-3 Ohms
reading
present?
YES
Mechanical
problem. Repair
or replace
clutch/pinion
assembly.
32
Go to step 3.
Is 10-12
VDC
present?
YES
If low resistance is
present in step 4,
NO
the problem is a
shorted field.
Replace pinion.
If an open in the
wiring is present,
check pinion
wiring
connections.
Go to step 1.
Does switch
test positive?
YES
Go to step 2.
Do you have
NO
proper engine
voltage?
YES
Go to step 5.
Does the
clutch
engage?
YES
Replace the
potentiometer.
Replace the
NO
switch.
Check wiring
from J1 and J2
for proper
connection. If
proper
connection is
NO
detected, repair
or replace engine
Connect
a test
transducer to
the board.
NO
Does the
clutch
engage?
Replace
the
YES
control
board.
Replace
the
transducer.
3A6400A
NO