90
Corrections
8.1 Replace the DIG-T2 board.
8.2 Fix the connections.
8.3 Disassemble the valve and check that the
plunger is free to move and that the seat
is clean and free from debris.
8.4 Replace the ANL-T2 board.
Possible cause check-up and tests
The problem may be a mechanical failure of
the valve, the valve driver located on the ANL-
T2 board or the control circuit on the
DIG-T2 board.
8.1 Check TP7. If the voltage is higher than
4V and the valve is open, then the DIG-
T2 board is faulty.
If the voltage at TP7 is <1VDC and the
valve is open, the problem is not the
DIG-T2, but some other element of the
system.
8.2 Check the connection between the
connector JP10 - 3 and the valve for a
ground short.
8.3 Remove the cover protecting the
terminals of the coil and check the
voltage across the coil when the solenoid
is connected. If the coil voltage is less
than 2V and the valve is open, there is a
mechanical problem.
8.4 If the voltage across the coil is higher
than 10VDC, then the ANL-T2 board is
faulty.
10. TROUBLESHOOTING (cont.)
10.4 In Process Malfunction (cont.)
Symptom
8. Air valve (43) is always
open.