New Holland T8010 Manual page 810

Troubleshooting
STEP 1
The PTO and diff lock valve can be serviced after the
cab is either raised or removed. See the Cab Raise/
Removal and Installation Section in this Service
Manual for procedure.
Before removing the valve, check the PTO controller
for fault codes. See the PTO Sections in this Service
Manual for procedure and corrective action if a fault
exists. Depending on which system is not functioning
correctly, see Power Take Off Control System How It
Works, or Differential Lock Control System How It
Works.
Section 35 - Hydraulic Systems, 3PT - Chapter 3
PTO AND DIFFERENTIAL LOCK VALVE
RH98F160
STEP 2
If other regulated pressure functions such as braking
or transmission control are not operating properly,
Check the regulated pressure. See the Hydraulic
Systems How It Works With Troubleshooting Section
of this Service Manual.
35-3-3