New Holland T8010 Manual page 1630

DIFF Lock Switch Failure
Cause:
DIFF LOCK switch failure.
Possible failure modes:
1. Switch failed.
2. External wiring failure (damaged wires, loose connectors, or bent pins).
3. Armrest controller internal failure (power supply or signal sensing failed).
Solution:
Monitor the switch status on the monitor screen of the service tool. Test the switch function, its wiring, and the
function of the armrest controller.
1. Open the armrest controller housing and disconnect connector SW203 for DIFF LOCK.
2. Test the DIFF LOCK switch and its wiring. Pay attention for wiring damage, loose connectors, or bent pins.
a. When the switch is in DIFF LOCK AUTO position, there should be continuity between pin 1 and pin 2 and no
continuity between pin 1 and pin 3.
b. When the switch is in DIFF LOCK ON position, there should be continuity between pin 2 and pin 3 and no
continuity between pin 1 and pin 2.
c. When the switch is in OFF position, there should be no continuity between any two of pin 1, pin 2 and pin 3.
If the switch is not functioning as specified above, replace the switch.
3. Check controller function:
a. Measure the voltage output from the controller at pin 2 of SW203. It should be at 12 VDC.
b. Short wire pin 1 to pin 2 to simulate the DIFF LOCK AUTO function. Short wire pin 2 to pin 3 to simulate the
DIFF LOCK ON function.
Monitor the switch status on the monitor screen of the service tool.
If the controller does not function properly, replace the armrest controller.
NOTE: See schematic section 44 on schematic poster.
Section 55 - Electrical System, Controller - Chapter 5
FAULT CODE ARM 1079
55-5-25