New Holland T8010 Manual page 1467

Wheel Slip Sensing Error In The Instrumentation Controller
Cause:
The percent slip is decided by the difference between the wheel speed and the ground speed. The AUX/Hitch/PTO
controller receives the slip signal information from the instrumentation controller through the Data Bus.
Possible failure mode:
1. Wheel slip sensing (radar gun, wheel speed sensor) failed (in most cases).
2. Percent slip calculation failed in instrumentation controller (small chance).
RADAR FUNCTION
The radar is connected to the vehicle electrical system through a 4 pin connector.
Pin A: GND
Pin B: SIG,
Pin C: B+
Pin D: Present
Pin A is the radar ground. Which is connected to the vehicle clean ground through SPL-C1.
Pin B is the radar signal. The signal is of square wave form with 'Low' 0.8 VDC or less and 'High' 3.7 VDC
minimum. Its frequency is scaled to 44 HZ/mph and proportional to ground speed. The signal is connected to the
ICU pin 13 CN-1 through connector C060 Pin 25.
Pin C is the power supply to the radar from Fuse 34 through connector C010 pin 83.
Pin D is the signal from radar to ICU indicating radar is connected to the system. It is connected to the ICU
connector CN-1 Pin 1 through connector C060 Pin 28.
Solution:
The wheel speed sensor and the radar gun (for the ground speed) are hard wired to instrumentation controller. If
the problem is with the wheel speed sender, then fault code AUX/Hitch/PTO 32 and AUX/Hitch/PTO 87 should be
recorded.
If there is no AUX/Hitch/PTO 32 and AUX/Hitch/PTO 87, the problem is most likely with the radar gun. There is
also a small chance of instrumentation controller malfunction.
1. Check the wiring of radar gun.
Disconnect connector C068 at the radar.
The power supply at pin C of connector C068 should be about 5 VDC when the tractor key is in the 'RUN'
position.
There should be good continuity from pin A of connector C068 to the clean ground.
Check for open circuit and wiring shortage.
2. Check the function of the radar.
The signal is from Pin B of the radar and connected to the pin 13, connector CN-1 of the instrument cluster
through Pin 25 of connector C060. The radar will detect the speed of any thing moving in front of it. So a quick
hand moving in front of the radar will be an easy way to test the frequency change of the radar signal. Special
tools (such as oscilloscope) is needed to check the frequency.
If the radar does not work as expected, replace the radar in the following procedures:
a. Disconnect the radar wiring.
b. Remove the radar from the vehicle.
c. Install the new radar.
d. Reconnect the wiring and check the function of the new radar.
3. If there is no problem with the radar and its wiring, check the function of the instrumentation controller and the
AUX/Hitch/PTO controller.
NOTE: Always inspect connector ends for damaged, bent or dislocated pins when troubleshooting.
NOTE: See schematic sections 24,25 and 26 on the schematic poster.
Section 55 - Electrical System, Controller - Chapter 3
AUX/HITCH/PTO FAULT CODE 86
55-3-48