14
309711
Pressure Control Repair
Motor Control Board Diagnostics
Note:
Keep a new transducer on hand to use for test.
CAUTION
Do not allow sprayer to develop fluid pressure with-
out transducer installed. Leave drain valve open if
test transducer is used.
1.
Remove four screws (18) and cover (39).
2.
Turn ON/OFF switch ON.
3.
Observe LED operation and reference following
table:
4.
Relieve pressure and un-
plug sprayer before servic-
ing control board
;
page 4.
LED
BLINKS
SPRAYER OPERATION
INDICATES
WHAT TO DO
Once
Sprayer runs
Normal operation
Do nothing
Once and
stays ON
Sprayer shuts down and LED stays ON
Motor open circuit or bad
control board
Check motor brushes and
armature. If OK, replace mo-
tor control board.
Two times
repeatedly
Sprayer shuts down and LED continues
to blink two times repeatedly
Run away pressure. Pres-
sure greater than 4500 psi
(310 bar, 31 MPa).
Replace motor control board.
See following
Motor Control
Board
procedure.
Three times
repeatedly
Sprayer shuts down and LED continues
to blink three times repeatedly
Pressure transducer is
faulty or missing
Check transducer connection.
Open drain valve. Substitute
new transducer for transducer
in sprayer. If sprayer runs,
replace transducer.
Four times
repeatedly
Sprayer shuts down and LED continues
to blink four times repeatedly
Line voltage is too high
Check for voltage supply
problems
Five times
repeatedly
Sprayer shuts down and LED continues
to blink five times repeatedly
Too much current
Check for locked rotor,
shorted wiring or motor. Re-
pair or replace failed parts.
Six times
repeatedly
Sprayer shuts down and LED continues
to blink six times repeatedly
Motor thermal switch
open circuit
Check for binding in pump or
drive. Check for bad motor.
