![background image](http://html1.mh-extra.com/html/karcher/kmr-1250-b/kmr-1250-b_service-manual_3518271043.webp)
43
KMR 1250 B, LPG, D
Troubleshooting Information
Note:
Troubleshooting may proceed with engine
shut off.
Check hydraulic unit
-
Check F3 fuse. The F3 fuse protects only the
hydraulic unit. It is located beneath the elec-
trical box.
-
Using a voltmeter, check input voltage of M2
hydraulic unit between thick red cable (pos-
itive polarity, 10 sq. mm cross-section) and
matching black cable (negative polarity).
-
Using the voltmeter, check input voltage on
motor relay. Perform measurement with ig-
nition switch set to position “I”.
With buttons S5 and S8 actuated, control
voltage must be present at relay.
If measurements removed components
and
produce a voltage reading but hydraulic motor
is not running, the hydraulic unit is defective and
must be replaced.
Note:
The wiring connections between relay and
hydraulic motor are not shown in the electri-
cal circuit diagram.
Check solenoid valves (Y1 / Y2)
Measurements
and
: Using the voltmeter,
check input voltage on solenoid valves Y1 and
Y2 at connecting plug.
If voltage is present, solenoid valves will switch
with an audible click.
If there is no voltage present, check power sup-
ply, vehicle ground connections and both but-
tons (S5 and S8) for proper functioning.
The solenoid valves are not available as spare
parts. If a defect is found, the entire hydraulic
assembly must be replaced.
Checking voltage on hydraulic unit
Checking F3 fuse
Hydraulic Unit – No Function
F3
(60A)
4
-S6
1
2
-S5
1
2
-Y2
-S7
1
2
4
5
-Y1
1
2
-F3
(60A)
-S8
4
5
-M2
+
-
-S10
-H2
M
1 qmm
(rt/bl)
(rt/bl)
(rt/bl)
1 qmm
(rt/bl)
0,75 qmm
(br)
10 qmm
1,5 qmm
(rt)
2,5 qmm
(rt)
1
2
0,75 qmm
(ws)
3
+
2
1
-
F3 Fuse, hydraulic unit
M2 Hydraulic unit
S5 Button, Two-Hand Operation
S6 Button, Lower Debris Container
S7 Button, Tilt Debris Container
S8 Button, Raise Debris Container
Y1 Solenoid valve, Tilt Debris Container
Y2 Solenoid valve, Raise / Lower Container