Piranha IRONWORKER P90, Operation Manual

Page: 26 / 53

Troubleshooting 26
P2: Machine Starts but Will Not Operate
Determine if the problem is electrical or hydraulic by using the manual override buttons
located on the Rexroth directional valve top and bottom sides. Refer to
Valve Body
Assembly Illustrated , pages 44 and 45, item 9. If the machine operates, the problem is
electrical. Continue with the below steps. If the machine does not operate on manual
override, the problem is hydraulic, and in this case continue with step 2 below.
1. If the machine operates, the problem is electrical. Follow the procedure below:
a. Determine if problem exists in the front control box only, the rear control box only,
or in both control boxes.
i. If problem is isolated to one box only, check the internal wiring and wiring
harness with disconnect plug for loose connection.
ii. If the problem exists in both boxes, follow the remaining procedures.
b. Check wiring connections in the electrical enclosure.
c. Check the valve body wiring harness, including the disconnect plugs, for loose
connections.
d. Check coils in the directional control valve.
2. If the machine does not operate on manual override, the problem is hydraulic.
a. Check to determine if the pump is developing flow. If not:
i. See if motor rotation is correct.
ii. Check motor / pump coupling (in models prior to S/N P3-5893) for tightness on
both shafts; and also check that insert is not damaged.
iii. Check hydraulic suction line for tightness.
iv. Check Oil level.
v. If the above checks out okay, the pump may be defective
b. Check to determine if the spool in the directional control valve is stuck in the center
position. If the valve is stuck, remove the end caps of the control valve and free
the spool. Inspect for contamination.