Pump Diagnostics - Graco LTS 15 Repair And Parts Manual

Control Board Diagnostics (ProLTS 17 and ProLTS 19)
NOTE: Check for motor problems before replacing control board. A damaged motor may burn out a good control
card.
Check for a damaged control board or pressure control
switch as follows:
1. Relieve Pressure, page 11.
2. Unplug electrical cord.
3. Remove four cover screws and front cover.
Remove motor enclosure.
4. Remove yoke and guide rods.
5. Remove gear.
6. Remove pressure control harness from control
board. Using tip of small, flat blade screwdriver,
press tab on right side connector to release.
Control Board Diagnostics (LTS 15 and LTS 17)
NOTE: Check for motor problems before replacing control board. A damaged motor may burn out a good control
card.
1. Unplug electrical cord and Relieve Pressure,
page 11.
2. Remove enclosure and check all control board con-
nectors for proper installation (see Wiring Diagram,
page 49).

Pump Diagnostics

When repairing or cleaning the pump, never submerge
pump in water or allow fluid to enter pressure control.
When pump packings wear, paint begins to leak down
the outside of the pump. At the first sign of leakage,
replace the pump or additional damage to the drive train
could occur.
313036N
NOTICE
Control Board Diagnostics (ProLTS 17 and ProLTS 19)
7. Attach harness from a pressure control switch you
know is functioning correctly to control board.
NOTE: Pressure control switch does not have to be
installed in pump.
8. Turn pressure control adjustment knob (C) +to max-
imum pressure setting.
9. Plug electrical cord into 120VAC receptacle.
10. Turn power switch (B) ON.
• If motor runs, replace pressure switch.
Pressure Control Switch Kit, page 28.
• If motor does not run, replace control board
repeat test. Control Board Kit, page 28.
3. Check fuse on control board. If fuse is blown, deter-
mine the cause before replacing control board (see
Advanced Troubleshooting, page 18).
1. LTS 15 and LTS 17: Replace pump using Pump
Replacement (Complete). See List of Kits,
page 28.
ProLTS 17 and ProLTS 19: Replace pump using
Pump Repair kit. See List of Kits, page 28.
2. If there is no paint leakage, see Advanced Trou-
bleshooting, page 18. Pump may not be defective.
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