104
Corrections
30.1 Replace the DIG-T2 board.
30.2 Fix the connections.
30.3 Disassemble the valve and check that
the plunger is free to move and that the
seat is clean and free from debris.
30.4 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.
30.1 Check TP13. If the voltage is higher
than 4V and the valve is open, then the
DIG-T2 board is faulty.
If the voltage at TP13 is <1VDC and the valve
is open, the problem is not the DIG-T2,
but some other element of the system.
30.2 Check the connection between the
connector JP10 - 9 and the valve for a
ground short.
30.3 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.
30.4 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
30. Slow exhaust valve (74) is
always open.