New Holland T8010 Manual page 1349

Interior Lighting and Horn System Symptom Chart
NOTE: The batteries must be fully charged and all connections clean and tight. Use a multimeter (DVOM) for these
tests.
IMPORTANT: DO NOT use a self-powered test light for any of these tests. Use of a self-powered test light can
cause damage to components in this system.
WARNING: Before performing any of the electrical tests, be sure all operating controls are in neutral or
!
park lock position. This will eliminate accidental movement of the machine or start-up of power driven
equipment.
Interior Lighting and Horn System Diagnostic Tests
NOTE: The batteries must be fully charged and all connections clean and tight. Use a multimeter (DVOM) for these
tests.
IMPORTANT: DO NOT use a self-powered test light for any of these tests. Use of a self-powered test light can
cause damage to components in this system.
WARNING: Before performing any of the electrical tests, be sure all operating controls are in neutral or
!
park lock position. This will eliminate accidental movement of the machine or start-up of power driven
equipment.
Test Point
1 Ignition in Run position.
Measure voltage at horn
connector 412A.
2 Measure voltage at in-line
connector 409 terminal A.
3 Measure voltage at in-line
connector 333 terminal 4.
4 Measure voltage at in-line
connector 10 terminal 80.
5 Measure voltage at fuse
#17.
6 Measure voltage at splice
fuse 16.
Section 55 - Electrical System - Chapter 1
A - Horn System Circuit Test
Good Reading
12 volts
If good reading, go to test
point 7.
12 volts
If good reading, repair
open in 722D(R) circuit.
12 volts
If good reading, repair
open in 722C(R) circuit.
12 volts
If good reading, repair
open in 722B(R) circuit.
12 volts
If good reading, repair
open in 722A(R) circuit.
12 volts
If good reading, repair
open in J9 circuit.
55-1-168
Possible Cause of Bad Reading
Open in unswitched B+ circuit to horn.
Go to next test point.
Open in unswitched B+ circuit to horn.
Go to next test point.
Open in unswitched B+ circuit to horn.
Go to next test point.
Open in unswitched B+ circuit to horn.
Go to next test point.
Fuse #17, or
Open in unswitched B+ circuit.
Go to next test point.
Open in 101B(R) circuit from
unswitched B+.