74/78 Troubleshooting
Bosch Rexroth AG, Control block SB24/34, RE 66170-B/2019-05-15
14.2 Malfunction table
Within the admissible operating conditions, no malfunctions occur at the control
block/control block segment.
Table 37: Malfunction table
Fault number
Fault
Origin and/or location of the fault
Remedy
F1
Hydraulic fluid leaks from the
control block segment
Damaged sealing element
Replace sealing element
Control block segment housing damaged
Replace the control block segment
F2
Hydraulic fluid is leaking at the
supply line and/or port to the
control block segment
Sealing element damaged
Replace sealing element
Pipe or hose lines damaged
Replace pipe or hose lines
Loose pipe or hose lines
Tighten the fittings
Control block segment housing damaged
Replace the control block segment
F3
Hydraulic fluid is leaking between
the control block segments
Dirt or foreign particles
Clean the flange surface
Sealing element damaged
Replace sealing element
Loose tie rod screws
Check the tightening torques
Damaged flange surface
Replace the control block segment
F4
Fluctuations in pressure and flow
Pressure oscillations in the system
Ventilate the control block segments
Ventilate the hydraulic system
Dirt or foreign particles in the control
block segment
Clean the inside of the control block segments
Ensure prescribed cleanliness of
hydraulic fluids
F5
Excessive temperature at the
control block segment
Excessive ambient temperature
System-related/remedy by external measure
Hydraulic fluid temperature too high
Lower hydraulic fluid temperature
Excessive flow
Reduce flow
F10
No function
Control block segments connected incorrectly Correct hydraulic ports
Electric components connected incorrectly
Correct electric ports
No hydraulic fluid
Ensure hydraulic fluid supply
Dirt or foreign particles in the control
block segment
Clean the inside of the control block segments
Ensure prescribed cleanliness of
hydraulic fluids
In case of malfunctions caused by contamination, it is essential to check and
possibly improve the quality of the hydraulic fluid through appropriate measures,
such as purging, exchange or additional installation of filters in addition to
carrying out repairs.