New Holland T8010 Manual page 1350

Test Point
7 While pressing horn switch
(on universal switch),
measure resistance from
horn connector 412B to
ground.
8 While pressing horn
switch, measure
resistance from in-line
connector 409 terminal B
to ground.
9 While pressing horn
switch, measure
resistance from in-line
connector 333 terminal 12
to ground.
10 While pressing horn
switch, measure
resistance from in-line
connector 60 terminal 16
to ground.
11 While pressing horn
switch, measure
resistance from in-line
connector 51 terminal 9 to
ground.
12 While pressing horn
switch, measure
resistance from universal
switch terminal 220H to
ground.
13 Measure resistance from
universal switch terminal
220J to ground.
Section 55 - Electrical System - Chapter 1
A - Horn System Circuit Test
Good Reading
Less than 1 ohm
If good reading, horn
power and ground circuits
okay. If horn does not
work, replace horn.
Less than 1 ohm
If good reading, repair
open in 723D(B) circuit.
Less than 1 ohm
If good reading, repair
open in 723C(B) circuit.
Less than 1 ohm
If good reading, repair
open in 723B(B) circuit.
Less than 1 ohm
If good reading, repair
open in 723(A) circuit.
Less than 1 ohm
If good reading, repair
open in 9A(B) circuit.
Less than 1 ohm
If good reading, replace
universal switch.
55-1-169
Possible Cause of Bad Reading
Open in switched ground circuit from
horn.
Go to next test point.
Open in switched ground circuit from
horn.
Go to next test point.
Open in switched ground circuit from
horn.
Go to next test point.
Open in switched ground circuit from
horn.
Go to next test point.
Open in switched ground circuit from
horn.
Go to next test point.
Open in switched ground circuit from
horn.
Go to next test point.
Open in circuit from universal switch
terminal 220J to ground.