308-209
16
MOTOR WON’T OPERATE
.
TYPE OF PROBLEM
WHAT TO CHECK
If check is OK, go to next check
WHAT TO DO
When check is not OK refer to this column
Condition B
(continued)
Both lamps off
6. Check motor thermal cutout switch. Connect
volt meter to TP6 female and TP9 female.
Plug in sprayer and turn on. Meter should
read 105 to 125 V AC. Turn off and unplug
sprayer.
6. Allow motor to cool. Correct cause of over-
heating. If switch remains open after motor
cools, check continuity between TP9 fe-
male and TP10 with ohmmeter. If open, re-
place motor.
REFER TO THE WIRING
DIAGRAM BELOW TO
IDENTIFY TP POINTS.
7. Check microswitch (302).Reconnect TP6
connectors.Connect volt meter to TP15 male
and TP4. Meter should read 50–125 VAC.
7. Clean microswitch male terminals. Replace
loose or damaged terminals. Securely
reconnect leads.
8. Visually inspect microswitch (302) button. Ad-
justment stud should not depress button
when fluid pressure is zero. Depress button
with small screwdriver; audible click indicates
microswitch is in normal position.
8. Microswitch is faulty. Return sprayer for
repair.
9. Check microswitch (302) continuity with ohm
meter.
Be sure sprayer is unplugged! Meter
should read zero ohms with no fluid pressure
in the sprayer.
9. Microswitch is faulty. Return sprayer for
repair.
10.Check all terminals for damage or loose fit.
Reconnect TP6 connectors.
10.Replace damaged terminals and recon-
nect securely.
11.Check circuit board (79) by substituting with
a good board. See page 26.
11.Replace circuit board. See page 26.
Condition C
Red lamps on,
Clear lamp off
Unplug sprayer!
1. Check circuit board (79) by removing from
box
without disconnecting wires; see page 26
for removal procedure. Place thin cardboard
in optical detector slot. Plug in and turn on
sprayer
ONLY LONG ENOUGH TO CHECK
LAMP CONDITION.. Clear lamp should be on
now. Turn off and unplug sprayer . Remove
cardboard.
WARNING:
Removing circuit board while still
wired over–rides optical detector and may cause
sprayer to over–pressurize, if microswitch does
not function properly.
WARNING:
To reduce risk of electric shock,
handle board by edges only! Do not allow any
metal objects to come in contact with board!
1. Replace circuit board. See page 26.
2. Check bourdon tube flag and detector posi-
tion. Reinstall circuit board (see page 26).
Turn pressure setting to maximum; flag
should extend less than half way into optical
detector slot from the top.
2. Perform pressure control adjustment to
see if that corrects problem. See page 28.
If not, replace bare pressure control box
(301). See page 27.
OPTICAL
DETECTOR
CIRCUIT
BOARD
FLAG
WIRING DIAGRAM
306
303
309
308
TP6
TP16
TP10
TP9
TP14
TP13
TP7
TP15
MOTOR
LEADS
NOTE:
These leads have
interchangeable
connections:
TP9
and
TP10
TP13
and
TP14
TP15
and
TP16
AC1
AC2G2
_
+
WHITE
BLUE
YELLOW
RED
GREEN
BLACK
WHITE
THERMAL SWITCH
GROUND
WIRE
BLACK
POWER SUPPLY CORD
MOTOR
302
TP8
G1
TP1
TP2
TP3
TP4
