Hello Folks..1981 Ford F-150 Ranger / 351M engine. Horn does not work...button tests good with volt meter...wiring looks good into fuse box...but no diagram on or near fuse box...any ideas on the correct amperage and location of the horn fuse. Thanks. Ken

Also engine dashboard lights stay on ???? Check engine light ? As far as the wipers & washers an horn not working - viewing wiring diagrams for those thing's an testing with a DVOM - digital volt ohm meter is the way a professional technician would find the problem. Seeing if they share a power supply or a ground . Do you know what these are ? Free wiring diagrams here http://www.bbbind.com/free-tsb Enter vehicle info. Year , make , model an engine size. Under system click on body & accessories ,then under subsystem click on wipers / washers . Click the search button then the blue link's one at a time . Looking at the diagram i see a electronic control module is involved . (GEM) generic electronic module . Your best bet would be to take it to a qualified repair shop.

Do you know how to test automotive electrical circuits ! Using a wiring diagram and a volt meter ? test power to the wiper motor .
Control from the switch .
http://www.bbbind.com/free_tsb.html free wiring diagrams . Enter vehicle info. year , make , model an engine size . Under system click body & accessories , subsystem click wiper / washer . click the search button then the blue link . Look at the diagram for pin # 's an wire colors , see fuse at top of diagram . Check B+ power with volt meter . Check the inputs from the wiper switch to the motor . If all the power an inputs are good , replace the wiper motor .

Hi there:
I suggest to check this diagram on...
Ford Engines: 5.0L HO, 351W, 351M, 351C, 400




Ford Engines: 5.0L HO, 351W, 351M, 351C, 400:
Rotation: Counter-clockwise
Firing Order: 1-3-7-2-6-5-4-8

Hope this helps; also keep in mind that your feedback is important and I`ll appreciate your time and consideration if you leave some testimonial comment about this answer.

Thank you for using FixYa, have a nice day.

Hi there:
I suggest to check this diagram on...
Ford Engines: 5.0L HO, 351W, 351M, 351C, 400




Ford Engines: 5.0L HO, 351W, 351M, 351C, 400:
Rotation: Counter-clockwise
Firing Order: 1-3-7-2-6-5-4-8

Hope this helps; also keep in mind that your feedback is important and I`ll appreciate your time and consideration if you leave some testimonial comment about this answer.

Thank you for using FixYa, have a nice day.

Well it depends on what you tested in the circuit most horns are vary simple they have a 12 volt wire hot and it goes through the horn to ground . If you put your muilty meter on OHMS and touch the red lead to the +side on the horn and the black lead to the ground side the meter should read 000 or vary low resistance if not go to the frame with the black lead if it reads 000 or differane from the last test then the horn is bad. Next test the power supply to the horn so put the meter on the 20 volt DC. scale unplug the wires from the horn and see if you have 12 volts or any voltage comeing to the horn you may have to turn the key to run depending on how its wires but if the blinkers work the horn should to . You likely have more then 1 horn so look around in there make sure of what your doing or the tests will be no good . If you have no power at this point check the fuse box for a burnt out fuse it won't be a big amp fuse mabey 10 amps and may not say horn. Im sorry i don't know exactly ware the relay is on a 2008 focus but it would be in whats called a relay center witch you likely would be able to find in the oweners manual in the glove box . But the horn is rarely used and most likely a connection problem they tend to be low on the vehicle and get wet along with road salts in the winter depending ware you live can get corroided . But if your going to test make sure the test is going to give you the information you need to correctly daigonis the problem Good luck

The horn button supplies a ground to the horn relay.Start by pulling the plug at the base of the column,see if you can get a ground on one of the pins from the column when you pus the button.Or find the horn relay,and do the same test from there.You should find 12v on one on the relay socket pins,a ground on one(this will be the wire to the horn)and a ground on the 3rd pin when you press the horn button.

Click over diagram for zoom...

Fig. 6: Vacuum schematic - 351M engine

Fig. 7: Vacuum schematic - 351M engine


Hope this helps (remember to rate and comment this answer).

Did you check the fuse for the horn ?

Next, check the horn connector with a meter ( set to DC volts ) and have someone press the horn button, you should get + DC at the connector.

If not, pull the horn relay, and jumper the normally open contact ( red line in the diagram below )


With this jumpered, and the horn fuse good, the horns should sound. If not, recheck the fuse or could be an issue with the horn connector.

1. Did you check the fuse for the horn ?
This is Engine Compartment Fuse # 7 ; 20A

2. You can pull the Horn relay and jumper the normally open contacts ( as shown with the red line below ) to activate the horns without using the button.


If this does not work, either the fuse is no good, or the ground at the horn connector is no good. Replace the fuse or test the ground on the horn connector with a meter ( set to ohms ) to the battery neg terminal.

If this does work, using a meter ( set to ohms ) test from pin #2 in the relay socket ( as shown above ) to the battery neg terminal. When you press on the horn button, you should have a low resistance ( The test steps will stop you from paying for basic trouble shooting issues.

On this website you find fuse box diagram and description for Ford Ranger (1995)

https://www.carknowledge.info/ford-ranger-1993-1997-fuse-box-diagram/

https://www.autogenius.info/ford-ranger-1993-1997-fuse-box-diagram/