The diode is not really necessary. It is used to cutdown on the "electrical noise" for the Military Radios.
I tried a search and found warthogs pics on the relays and diodes. If i remove the diode in the harness in the pics would i have any problems? Can i test is with a multimeter?
The diode can be checked with a multimeter. You will have Zero ohms with the leads connected one way and an open circuit with the leads reversed.
Also the Suppressor/capacitor at the horn is also used to reduce noise for the Military Radios.
The horn circuit is very simple.
12v is fed to the Horn Relay via the Orange wire.
The Horn button grounds the circuit to energize the relay via the Black wire.
When energized the relay closes and sends 12v to the horn via the Dark Green wire. This wire passes thru the firewall at the Main Terminal Block next to the steering column.
Things to check:
Voltage from the fuse box to the relay. You should have 12v with the key on. Make sure the fuse is good.
I have power at the relay. Mabye i'll jump it there and see if works?
You can remove the relay and jumper between the orange wire and the green wire. That will send the 12v directly to the horn.
Black wire from the horn button to the relay. Disconnect the relay and check the ohms when you press the button. The problem could be the horn button or the steering column connection.
Green wire. Check the ohms between the Horn Relay and the connector at the horn "before" the suppressor/capasitor. The only connectos are the firewall connection block and at the suppressor.
Check the suppressor at the horn. They do age and go bad. They are used on the wipers, heater motor, alternators and the horn. You might need to remove it.
