New Holland T8010 Manual page 1514

PTO Speed Is Detected When The PTO Is In The Off State Without Engine
RPM
Cause:
The PTO controller monitors the PTO clutch output speed. This fault code is recorded if the PTO controller has
detected PTO shaft rotation when engine is off.
Possible failure mode:
1. Implement attached to tractor caused the PTO to turn.
2. PTO speed sensor or its wiring harness failure.
PTO SHAFT SPEED SIGNAL
The PTO shaft speed frequency is derived from a variable reluctance speed sensor in the transmission. The clutch
speed sensor is connected directly to the AUX/Hitch/PTO control module. The sensor output is directly proportional
to PTO clutch output speed, and is a quasi-sinusoidal wave form the amplitude of which is non-linearly proportional
to speed. The amplitude range of the signal is from 3 volts peak-to-peak to 80 volts peak-to-peak centered around
chassis ground. Frequency range is from zero to 3,200 Hz worst case.
PTO SHAFT SIZE SPEED SIGNAL
The PTO shaft size speed frequency is derived from a variable reluctance speed sensor in the transmission. The
sensor is connected directly to the AUX/Hitch/PTO control module and its output is proportional to PTO clutch
output speed, but scaled differently from the PTO clutch speed signal depending upon which PTO shaft is in use;
i.e. 1-3/4" 1000 RPM, 1-3/8" 1000 RPM or 1-3/8" 540 RPM. The signal is a quasi-sinusoidal waveform the
amplitude of which is non-linearly proportional to speed. The amplitude range of the signal is from 3 volts peak-to-
peak to 80 volts peak-to-peak centered around chassis ground. Frequency range is from zero to 760 Hz worst
case.
Solution:
Make sure the implement attached to tractor is not causing the PTO to turn. Test the PTO speed sensor and its
wiring harness.
1. Make sure the implement attached to tractor is not causing the PTO to turn.
2. Restart the tractor after PTO switch moved to OFF position. Turn PTO on and off to check the shaft spinning.
3. Monitor the engine speed and PTO speed either at Instrument cluster or using the service tool. If there is no
engine speed display when the engine is running, go to step 4. If there is PTO speed display when the engine
is not running, go to step 5 and 6.
4. Check the engine RPM signal.
a) Check the engine RPM signal wiring. There should be good continuity between cavity 33 of AUX/Hitch/PTO
controller connection C057 and the terminal W of the alternator.
b) Check the engine RPM signal at terminal W of the alternator.
5. Check the wiring harness to the PTO shaft speed sensor.
Check the continuity from Pin 20 of connector C058 to Pin A of connector C145.
Check the continuity from Pin B of connector C145 to the chassis ground.
6. Check the function of the PTO speed sensor. It should have resistance of about 3 K ohms.
NOTE: Always inspect connector ends for damaged, bent or dislocated pins when troubleshooting.
NOTE: See schematic sections 49 and 50 on the schematic poster.
Section 55 - Electrical System, Controller - Chapter 3
AUX/HITCH/PTO FAULT CODE 165
55-3-95