New Holland T8010 Manual page 1590

Communication lost with the armrest controller
Cause:
Communication lost between transmission controller and armrest controller.
Possible Failure modes:
1. Bad Can Bus connection between the transmission controller and armrest controller.
2. Controller failure.
Solution:
Make sure both the transmission controller and armrest controller are functioning OK.
Check the Data Bus connections.
1. Check the function of the Armrest controller:
A. Make sure the connector C137 to the Armrest controller is plugged in
B. Check the LED light on the Armrest controller
LED light on - failed controller, replace the controller.
LED light flashing - controller is OK
LED off - no power to controller, check power supply and its fuse.
NOTE: The LED light for the Armrest controller is located on the controller circuit board. It can be seen by looking
through the opening next to connector C137 from the rear of the Armrest.
2. Check the function of the transmission controller:
Make sure there is no other fault code or symptom indicating transmission controller malfunctioning.
3. Check the power supply to the Tractor Data Bus.
A. Check fuse #42.
B. Turn the tractor key switch to the ON position. Verify approximately 12 volts power at fuse #42. If no power,
check the power supply to the key switch power stud.
4. Check the Tractor Data Bus at the can bus resistor terminators.
The following checks are performed looking into one end of the data bus and checking the resistor terminator
at the other end.
A. Check from the can bus resistor terminator at the engine. Raise the tractor hood. The resistor terminator is
located in harness that leads into Buss box. Disconnect the terminator plug at connector C205. With the
key switch in the ON position, measure the voltage on each pin to ground on connector C205.
At cavity A, the yellow wire, it should read from 2.5 to 2.8 volts.
At cavity B, the green wire, it should read from 2.2 to 2.5 volts.
If the above checks are ok and all controllers came online, it means that the opposite end resistor
terminator and the data bus wiring are functioning correctly. The engine end resistor terminator has most
likely failed. Test the engine end resistor terminator and replace if it has failed.
B. Check from the can bus resistor terminator in the AUX/Hitch/PTO controller.
Reconnect the engine end resistor terminator and disconnect the AUX/Hitch/PTO controller connector
C053.
With the key switch to OFF, then to ON. Measure the voltage between the following cavities at connector
C053.
At cavity 15, the yellow wire, it should read from 2.5 to 2.8 volts.
Section 55 - Electrical System, Controller - Chapter 4
FAULT CODE TRANS 135
55-4-63