JD 320 - Hydraulics OFF

[Mainiac123]

Hi All, Picked up a 2006 320 with 2500 hrs at auction. Had to jump it and work the brake switch a lot to get brake to release and then load up. The hydraulics wouldn't activate so no boom or bucket and both pedals locked. Working on it three days now and no change. Cleaned and ohmed brake switch pins - good. Cleaned up ground in back top left corner of cab and near battery. Cleaned, bent blades in fuse block back into place, and reinstalled - good to go. Brake, Boom, and Bucket solenoids all have continuity but haven't jumpered to 12v to really test. "Hydraulics OFF" indicator in control panel still won't go out. Wiggling Brake switch in center position while pressing boom pedal got the indicator to flash and slight clicking from control valve. Got boom to lift a couple inches but not enough to get bad battery out. Anyone have an idea what to try next? Are there more grounds to check/clean? Could the boom release T-handle by left shin be involved? Any help or pointer much appreciated. Maine Native.

 

[Mainiac123]

Ran extra ground wire from cab ground to battery ground point and replaced park switch. Checked wires in console a third time; no damage found. Still no change. Cracked boom lines and jacked boom enough to replace battery. Parking brake releasing now and working like it's supposed to. Guess it likes having it's own clean 12v? Still won't activate hydraulics but hearing a solenoid click near the control valve when moving brake switch from on to center position. Port solenoid? Not sure. Trying to get a mechanic to look at it when they get time. Until then... Anyone have thoughts or suggestions?

 

[Mainiac123]

Ran extra ground wire from cab ground to battery ground point and replaced park switch. Checked wires in console a third time; no damage found. Still no change. Cracked boom lines and jacked boom enough to replace battery. Parking brake releasing now and working like it's supposed to. Guess it likes having it's own clean 12v? Still won't activate hydraulics but hearing a solenoid click near the control valve when moving brake switch from on to center position. Port solenoid? Not sure. Trying to get a mechanic to look at it when they get time. Until then... Anyone have thoughts or suggestions?

Figured it out! Turned out to be several things that all needed to be fixed to get it to work. The heavy equipment mechanic tried his best for two hours but was stumped too. The best thing we did was get the manuals for the machine. "A++ Manual Store" had the best prices and the downloads came through with no problems. The schematics show all the connectors and splices and their locations in the harness too. So 1) direct ground added from cab to chassis, 2) new battery with plenty of CCA, 3) tab on connector X2 (main harness) broken and had short pins (cleaned, reconnected fully, tie-strapped tight) 4) connector W5 had dirt in it on solenoid wire H01 side (cleaned, reconnected), and finally 5) bucket solenoid had some resistance and clicked but the computer treated it as a short to ground. Result: the computer shutdown the signal to all three solenoids a half second after sensing the "short". Ordered a new solenoid and will replace when it arrives. In the mean time, disconnected it and put it back in after grinding off the tab. I know, but I'm the only operator and the port solenoid still blocks any oil flow even if I move the pedal by accident. Sorry to be long winded but wanted to share the whole story and the fix in case someone else has similar issues. One plus? I know the machine inside and out now. Hope that helps down the road.