DeWalt DP3900, GX390 English, Possible Cause, Possible Solution, Troubleshooting Codes cont

(Troubleshooting Codes cont.)

CODE	POSSIBLE CAUSE	POSSIBLE SOLUTION
17	Spray wand not in low pressure.	See Spray Wand Nozzles under Operation.
18	Chemical filter clogged.	Clean filter.
19	Chemical screen not in cleaning solution.	Make sure end of chemical hose is fully submerged into cleaning
		solution.
20	Chemical too thick.	Dilute chemical. Chemical should be the same consistency as water.
21	Worn seal or packing.	Have parts cleaned or replaced by authorized service center.
22	Chemical build up in chemical injector.	Have replaced by an authorized service center.
23	Worn or obstructed valves.	Have replaced by authorized service center.
24	Worn unloader piston.	Have replaced by authorized service center.
25	Worn or broken o-ring.	Check and replace.
26	Loose hose connection.	Tighten.
27	Piston packings worn.	Have replaced by authorized service center.
28	Pump head or tubes damaged from freezing.	Have replaced by authorized service center.
29	Oil seals worn.	Have replaced by authorized service center
30	Loose drain plug.	Tighten.
31	Worn drain plug o-ring	Check and replace.
32	Worn fill plug o-ring.	Check and replace.
33	Pump overfilled.	Check for correct amount.
34	Incorrect oil used.	Drain and fill with correct amount and type of oil.
35	Vent plug is clogged.	Clean vent plug; blow air through it to remove any blockage. If
		problem persists, replace plug.
36	Defective E-Z start valve.	Have replaced by authorized service center

English

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