1999 PUTZ 28  GOING THRU POH CARDS. PUMP HAS BEEN TO LOCAL REPAIR SHOP THREE TIMES   3 POH CARDS  LAST TIME ALSO 2 PROX SWITCHES AND FOUR WAY PLUG PROXIMITY SWITCHS PLUG INTO.  HAVE TESTED DIODES SHOWN TO BE IN THAT CIRCUIT ONE TESTED BAD AND WAS REPLACED..

   WHEN I BOUGHT THE MACHINE IT HAD A 20 AMP FUSE IN POSITION 2F49 WHICH FEEDS POH. CARD  SHOULD HAVE BEEN 5 AMP WE NEVER CHANGED IT  NOW AFTER CHANGING CARDS AND ATTEMPTING TO PUT RIGHT FUSE IN IT (5 AMP) FIND IT BLOWS ANYTHING UNDER 15 AMP, IMMEDIATELY.  USING METER CALLED aMP HOUND WE FIND AMPERAGE AT FUSE SPIKES TO AROUND 20 AMPS WHEN PUMP IS ENGAGED AND EACH TIME IT CYCLES OFF PROXIMITY SWITCHS (BOTH).

   TESTING WIRES ON POH 1-10 NONE SHOW SPIKE ACCEPT #10.  WHICH IN DRAWING HAS TWO OF THE DIODES IN LINE. TESTED- REPLACED ONE  

ANY ADVISE  LOCAL TECH OUT ON VACATION  LAST I HEARD FROM HIM WAS HE THOUGHT PROBLEM POSIBLY REQUIRING REPLACEMENT OF  WIRING LOOM OR CONTROL PANEL -COMPLETE PANEL!!   

Sounds like a frayed wire is earthing somewhere on the chassis or internally within a cable loom(s). Or maybe perhaps someone has used a 24v part on a 12 volt system or vice versa? 

Pin 10 is the output to the poh valve.  You should see a spike of 80-170ms each stroke when the prox switches trigger or when you hit your stroke change switch.   

The problem is likely in diodes in the panel or the wire from the x88 cable out to your prox switches, connectors for valves at the water box, and boom valves.  

Use your multi meter on the diodes - disconnect one of the two wires from the diode to eliminate interference from the circuit.  On the diode test setting You should get 0.5v in one direction and 0 in the other.    

If they’re all good, the wire from x88 to the prox switches might be shorted, or the wires to the pumping valves.   Run new ones (pin them out and test them first).   If you change the panel you might have the same problem so save some money and spend some time to diagnose 

UPDATE..   NEW WIRING FROM (X88) control panel to poh valve and proximity switch block. 2 diodes changed. Still drawing 7+ amps so not all taken care of yet.  But down from the around 17 amps it was drawing.poh coil unplugged no difference. Still shows all the draw on wire 10 of poh. Supposed to be under 5 amps (5 amp fuse feeds ).

Up and running finally. Thanks to putz tech support. Problem is in safety switch for hopper. Instead of cutting off poh it burns it up.. unplugged for now..