Karcher HD 6/16-4 M / MX Service Manual - page 24
24
English
5.906-246.0 Rev. 01 (09/14)
9
Troubleshooting
Findings
Possible cause
Correction
Appliance is not running
Power supply interrupted
Check connection cable for damages.
Check the supply voltage.
Engine is overheated
Turn device switch on "0" and let engine
cool off for min. 5 minutes.
Power switch
Check/replace the appliance switch.
Pressure switch
Check/replace the pressure switch.
Appliance is not building up pressure
Nozzle soiled
Set nozzle to "High pressure".
Clean the nozzle.
Replace the nozzle.
Air within the system
Vent appliance.
Insufficient water quantity
Check water supply level (refer to tech-
nical data).
Suction area blocked
Clean the sieve in the water connection.
Check all inlet pipes to the pump.
Pressure interruption
Check the pressure and suction valves
for leaks / replace.
Check / adjust/ replace overflow valve.
Device turns on and off while hand
spray gun is closed
Tightness of system
Check the trigger gun and the O-rings
on the high-pressure hose for leaks / re-
place.
Pressure interruption
Check / adjust/ replace overflow valve.
Check / replace the pressure retaining
valve.
Check / replace the pressure switch /
control piston.
Appliance does not switch off when the
hand-spray gun is closed
Pressure interruption
Check / adjust/ replace overflow valve.
Check / replace the pressure retaining
valve.
Check/replace the pressure switch.
Check / replace the pressure switch /
control piston.
Detergent is not being sucked in
Low or no detergent flow
Set nozzle to "CHEM".
Check/ clean detergent suction hose
with filter.
Open or check/clean detergent dosing
valve.
Check / clean / replace the detergent
check valve.
Check / replace nozzle for detergent.
Replace detergent injector.
Pump leaky
Water leak between the cylinder head
and the piston casing
Check / replace high pressure and low
pressure seals.
Oil leaks between the cylinder head
and the piston casing
Replace oil seals.
Check / replace piston.
Pump is vibrating
Pipes
Check suction pipes for water and de-
tergent and ensure that they are leak-
proof.
Dosing valve
Close dosing valve for detergent to op-
erate the machine without detergent.
Air within the system
Vent appliance.