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TR2/3/3A Tr3 horn testing and wiring

Dave L

Freshman Member
Country flag
To All,
i am trying to test my horn button after repairing the brass contact on the horn as my horn would not go off. How do i test the horn push with a test light? i get 12 volts constant to the two NG wires on either side but i get no light when i probe either NB wires? I have tried with the ignition on and off.
Thanks in advance.


Country flag
If you pull the horn wire at the end of the steering gear (pull it out of the connector leading up to the horns) and test the side going to the steering gear with an ohm meter you should read infinite ohms...i.e. an open circuit. The same test while pressing the horn button should be very low, like 1ohm or less. If those readings are good, then you can re-connect the wire and move up the circuit to the horn connections.

Another check...where you pull the horn wire at the steering gear, if you test the side going to the horns, they should read 12v compared to ground (be sure to switch your tester to volts!). If you do not get the 12v on that side of the connector, then check your fuse first. If the fuse is good, then follow the connectors until you find one that is not seating fully.

If you follow the connections and are getting 12v into the horns, but not back out the other wire from the horns...then you have an internal problem with your horns.


Country flag
I think you will find the NB side is the ground side of the circuit and will not show voltage. I think you should be able to hotwire the horn right at the horn for moment to see if it works.

Dave L

Freshman Member
Country flag
Thanks to all,
i checked both sides with the meter and all is ok. Does anyone have pictures of the wiring for them? i see the 4 wire connector on the drivers side and the single connector for the passenger side but i am not sure how to hook up the drivers side. On the passenger, the constant hot from the fuse goes into the larger female connector and the smaller wire into the smaller female connector but I am not sure of the drivers side.
Thanks again for all the help.


Jedi Trainee
Country flag
Do you have the wiring diagram in the service manual? F6CD450F-2F52-4743-BA84-DA1AA844B008.jpg
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