Digital Display Messages - Graco GMAX II 3900 Repair Manual

WARNING
Relieve pressure before repair, page 5.
DISPLAY* SPRAYER OPERATION
No Display Sprayer may be pressurized
Sprayer may be pressurized
ti6314a
Sprayer is pressurized. Power is
psi
applied. (Pressure varies with tip
bar
size and pressure control setting.)
MPa
ti6315a
Sprayer stops. Engine is running.
ti6316a
Sprayer stops. Engine is running.
ti6317a
Sprayer stops. Engine is running.
ti6318a
Sprayer stops. Engine is running.
(with constant
green LED)
Sprayer stops. Engine is running.
ti6320a
* Error codes also appear on control board as a blinking red
LED. LED is an alternate to digital messages.
1. Remove two screws (71) and swing down cover (130).
2. Start engine. Blink count is the same as error code(E=0X).
310893L

Digital Display Messages

•
•
INDICATION
Loss of power or display not
connected
Pressure less than
200 psi (14 bar, 1.4 MPa)
Normal operation
Exceeded pressure limit
Pressure transducer faulty,
bad connection or broken
wire
High clutch current
Loss of paint to pump or
severe pressure loss
Pressure greater than
2000 psi (138 bar, 14 MPa)
while in Flush Timer Mode
After a fault, follow these steps to restart sprayer:
1.
2.
3.
Digital messages are not available on all sprayers
Blinking LED total count equals digital error code
i.e., two blinks is the same as E=02
Check power source. Relieve pressure before
repair or disassembly. Verify display is
connected.
Increase pressure as needed
Spray
1. Check fluid path for clogs, such as clogged
filter
2. Open prime valve and gun if running
AutoClean
3. Use Graco paint hose, 1/4 in. x 50 ft
minimum. Smaller hose or metal braid
hose may result in pressure spikes.
4. Replace transducer if fluid path is not
clogged and proper hose is used.
1. Check transducer connection
2. Disconnect and reconnect transducer plug
to ensure good connection with control
board socket
3. Open prime valve. Replace sprayer
transducer with known good transducer
and run sprayer. Replace transducer if
sprayer runs or control board if sprayer
does not run.
1. Check wiring connections.
2. Measure: 1.2 +0.2Ω (GMAX II 3900);
1.7 +0.2Ω (GMAX II 5900/ 7900 &
TexSpray 7900HD)
across clutch field at 70°F
3. Replace clutch field assembly
1. Check for empty paint condition, clogged inlet
strainer, failed pump or severe leak
2. Reduce pressure and turn pump switch
OFF and ON to restart pump
3. WatchDog function can be deactivated by
turning WatchDog switch OFF
1. Open prime valve and gun
2. Verify no flow obstructions or clogged filter
Correct fault condition
Turn sprayer OFF
Turn sprayer ON
Pressure Control
ACTION
15