Not sure what is going on with my RC valve.

I have the HRC loom, HRC box and PGM III. When following the set up instructions for the RC valves they do not open to 'hi' with the ignition on and the TPS unplugged.

The RC valve behaves correctly when I rotate the servo to 'hi' then turn the ignition on (it self closes).

I plugged my spare servo in and it behaves as normal;

Rotate to Hi and turn the ignition on - servo closes
unplug TPS and servo opens

I take it this means my original servo is knackered?