Graco magnum pro plus a20 Repair Manual page 22

Advanced Troubleshooting
Specific Problem
Sprayer wiring problems.
NOTE: Remove enclosure
mounting screws and pull
enclosure away from drive
housing. Take care not to pull
on leads from electrical cord
and power switch.
22
Cause
Sprayer power cord damaged. 1. Unplug sprayer power cord.
Sprayer power switch
damaged.
A60 diagnosis only: Motor
thermal overload cutoff switch
damaged.
WARNING: See Thermal
Overload on page 12.
Solution
2. Disconnect brown and blue power cord wires
at EMI filter.
3. Plug in power cord.
4. Test voltage between brown and blue wires of
power cord. Meter must read 220-240 VAC.
5. Replace power cord if no voltage.
1. Unplug sprayer power cord.
2. Disconnect both wires from power switch.
3. Check for continuity between switch
terminals.
4. Toggle switch ON and OFF. There should be
continuity in the ON position only.
5. Replace power switch if no continuity in ON
position.
1. Unplug sprayer power cord.
2. Remove motor harness from control board.
3. Check for continuity between yellow leads or
motor harness.
4. If thermal relief switch is open (no continuity)
allow motor to cool.
5. If switch remains open after motor cools,
replace motor using Motor Kit. See List of
Kits, page 30.
6. If thermal relief switch closes after motor
cools, find correct cause of overheating.
332697C