Graco Inc. 261820 Paint Sprayer User Manual


 
Pressure Control Switch Diagnostics
24 312667B
Pressure Control Switch Diagnostics
ProX7, ProX9, X5, and X7
If pressure control switch diagnostics reveal a damaged pressure control, replace it with the correct Pressure Con-
trol Switch Kit, see page 26. X5 and X7 sprayers have different pressure control kits because stall pressure is pre-
set at the factory.
1. Unplug power cord and Relieve Pressure, page 9.
2. If paint is leaking from pressure control switch
between pressure control knob and base, replace
pressure control switch.
3. ProX7 and ProX9: Remove front cover, yoke, and
pins. Disconnect pressure control switch connector
from control board.
X5 and X7: Remove enclosure and disconnect
pressure control switch connector from control
board. Use finger to support control board when
removing pressure control switch connector.
4. Use ohmmeter to check for no continuity between
sprayer ground and both pressure control terminals
in connector. If either pressure control switch lead is
shorted to ground, pressure control switch wires
have been pinched to ground during assembly and
pressure control switch needs to be replaced.
5. Use Ohmmeter to measure across two terminals in
pressure control connector. No continuity or open
circuit should exist when pressure control knob is at
lowest pressure setting (full counter-clockwise).
Replace pressure control switch if continuity exists.
6. Using ohmmeter to measure across two terminals in
pressure control connector. Continuity or closed
circuit should exist when pressure control knob is
set at maximum pressure (full clockwise). Replace
pressure control switch if no continuity exists.