I'm pretty sure that the fault codes should clear themselves whenever the fault has been rectified. It would be easy to test. Pull a plug off another sensor and see if it comes up with 2 codes. Then plug it back in and see if it clears. If its coming up with a code for Pump 2 pressure sensor, and it didn't change when you swapped the plugs then it would suggest an issue with the harness. And with you saying the fault is intermittent then as you say, the harness may have been good when you tested for continuity. Electrical issues are never easy to find unfortunately. I would firstly check the resistance up the signal wire and compare it to the resistance of the signal wire from pump 1. The resistance should be almost the same. Do the same with the V+ and gnd wires. Next you can test for continuity again and pull/tug the wiring harness to see if the continuity disappears. This may give you a rough idea the location of the fault. Out of interest, can you get the machine to fault at will? As in, if your testing will the 2 speed travel start and stop working during testing? One thing you could try is tap into the signal wire right at the multiplug at the controller and monitor the voltage. If you have both travel levers fully forward/reverse i'd expect to see a lower voltage reading. If the voltage goes high or reads 0 then that's the fault. For reference, the pump delivery pressure sensors need to read a low reading( it will fluctuate around 1-2v depending on pump load), the pump control sensors on the regulators should read a high voltage( around 4.5v) Another thing, is the auto idle working as it should? Will it decrease with the levers in neutral and increase when using the travel lever? I hope this is helping, i'd hate to think i'm leading you astray and it's a totally different fault. Also, i'd normally use MPDr to diagnose this. The checks with voltage checking is something i wouldn't normally do as i can see all the proper readings with MPDr. As for the local dealer. It all depends on the quality of engineer that looks at the machine. If he's had plenty of experience then he should find it without issue. Especially if he's using diagnostic equipment. Hope this info helps.