New Holland T8010 Manual page 1454

Hitch Lower Valve Threshold Is Too Low During Calibration
Cause:
During calibration, PWM threshold to start hitch lower is below the limit (6%).
Possible failure modes:
1. Lower solenoid coil resistance is too low.
2. Battery voltage is very high.
3. Valve failure.
Solution:
Make sure the calibration procedure is correct. Then do the following for troubleshooting.
1. Test battery voltage and the alternator output voltage (must be less than 14.7 volts DC).
2. Test lower solenoid coil (C152) and its wiring for low resistance.
Refer to fault code AUX/Hitch/PTO 5 troubleshooting procedures for details.
3. Make sure there is proper hydraulic pressure to the hitch valve.
Check for valve failure (center spring broken, spool too loose).
Repair or replace the spools or the valve according to the problem.
NOTE: See schematic sections 51 and 52 on the schematic poster.
The Time Allowed For Calibration Has Expired
Cause:
During calibration the time allowed for calibration has expired.
Possible failure modes:
Operator did not acknowledge (within 6 minutes) when hitch is fully lowered during calibration procedure.
Solution:
1. Recalibrate the hitch.
Section 55 - Electrical System, Controller - Chapter 3
AUX/HITCH/PTO FAULT CODE 52
AUX/HITCH/PTO FAULT CODE 53
55-3-35