Kalkomat Comboboxer Technical Information page 60

Solenoid Wires
Check resistance on these two terminals with a multi-meter. The
resistance should be very low around 0.5 Ω. If your meter shows
overload or infinite resistance the solenoid coil may be damaged. In
that case replacing the solenoid is necessary.
The solenoid can be evaluated in another way if for example you do
not have a multi-meter handy. This also involves unscrewing the
two terminals and pulling out the two wires. Instead of measuring
the resistance as described above make a temporary connection with
direct 12 V supply by touching the two wires onto the input voltage
terminal as shown in the picture below.
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