On removing the dummy plate on my Unit Adding valve base and testing individual air lines, I have determined that:
- This valve uses lines I, K, N, 0005, and 0075 (not J, K, N, 0005, and 0075 as my manual states).
- I had swapped two of the lines coming to this plate, causing my I and 0005 lines to be interchanged.
To fix problem number 2 I had to remove the mounting plate, disconnecting all the air lines, and re-mount it with the lines coming to the correct ports. I had tried just removing the two swapped lines but because of the way they were crossed I was unable to reposition them with all the other lines still in place.
Fortunately I found installing the plate much easier this time, perhaps because I inadvertently used a slightly different procedure.
On tracing all the lines I also found that my previous statement about the mould signalling (that it uses G and H) was incorrect; it actually uses H and J, which still does not match what the manual says.
I now have the rear pin block cover off and all the pins out for cleaning; once this is all reassembled and the remaining control valves are reinstalled I should find that all these airpins operate properly.