Recently started to work on a EX100-2 with multiple issues. Currently it will stall at relief or trying to dig. I am getting a code 26 for the DP sensor using my MPDR and have replaced this sensor twice with two known good sensors. Now for the fun issue when I unscrew this sensor form the valve block it is accompanied by a 5-10 second hiss of air pressure or vacuum coming from the hole and when the new sensor is installed the machine functions better but not fixed for a very short-lived time. Now I don't know if that's my issue or not. I am also only getting with a photo tach 2060 rpm reading on the crank in the high rev mode and my MPDR only states I'm getting 16 rpm all the time but no code for the engine speed sensor. I don't know how well my version of the MPDR works or the ZX2000 passcode software i got installed from some remote guy in China. Any help would be nice. Also Friday parts did send me an EC/PVC for a Ex120 not sure if that matters, they seem to think it's fine to use with an ex100-2. Things I have done are cleaned the fuel system, brass mesh filters at the injector connectors and tank, fuel filter, new P sensor, calibrated the angle sensor, new DP sensor, New PVC and EC, checked pressure switch function. I can't seem to find case drain on the pump and the Tech manual I have for the system tells me nothing for that pump.
Welcome to HEF gplopez10 . Not sure what manual you have, but a EX100-2 manual is Hitachi part # KM104E03 also possible marked as KM104-E-03 . There is no case drain on a EX100-2 hydraulic pump. An accurate engine speed reading at MPDR is critical. Resistance of the N speed sensor spec is 810 +/- 240 ohms. Using the AC voltage on a multimeter, the voltage at the two N sensor terminals should increase as the engine rpm increases. . To start troubleshooting DP sensor code 26. Using MPDr, What is the DP sensor pressure with engine at high idle and pilot controls in neutral ? With the DP sensor disconnected , What is the DP sensor pressure when shorting across machine wire harness terminals #1 and #2 ? See screenshot below.
it seems like it’s stuck at 24 degrees and it won’t de-stroke. This is the readings I’m getting and the engine speed sensor is functioning now. It will still kill it’s self at relief. I did short the harness and the dp readings are 2.6 as well as running at full throttle and idle with it connected.
Intermittent N speed sensor readings is possibly a poor harness connection issue at the N sensor. Looking at your (3) live data screenshots, If the pilot controls were in neutral , the dP pressure at 2.6 is normal. The pump angle sensor indicates 24.0 degrees but the PVC is looking for 5 degrees .The PVC is also grounding (or attempting to ground) the dn (down) pump displacement solenoid circuit. With engine running check for 24 volts at terminal #1 of both pump displacement solenoid valves. If voltage is ok, backprobe and ground terminal #2 of the “down” solenoid valve located furthest from the engine. See if the pump will de-stroke. See screenshot below for terminal id.
Okay, got function when grounding out the first solenoid. Did a ground check at the pvc, ec control and found them to be good 1 ohms +/- .3 . Also did a check from pvc to solenoid. Not sure what’s next.
Are you calling the "first solenoid" the one that is furthest from the engine ?
Yes
I would "load test " the wire from the down solenoid (furthest from the engine) to the pvc to confirm the wire can actually carry the solenoid coil load of approx 1.6 amps .