I have a 2000 Ford Ranger that I am attempting to repair for a friends teenage son. The main symptom is that Fuse #2 and #26 blow as soon as or shortly after the vehicle is started and the airbag light on the dash lights up and remains steady. Also, both headlights blew within 10 seconds of turning them on. I checked the voltage in the headlight socket and it reads 15.4v. This is the same reading I get at the battery with the truck running. Is this too high? I know my way around a vehicle fairly well mechanically, but unfortunatley, my electrical knowledge in minimal. I have a meter and can check the voltage on a connection, but that is about where my electriacl skills end. The battery is going bad and the truck has had to be jumped several times while troubleshooting. Could a bad battery cause these problems? Any help would be greatly appreciated. He doesnt have alot of extra cash for costly repairs, and I'm trying to help out however I can. I've spent countless hours reading Ranger message forums, but cant seem to locate a solution. I'm very thankful that forums such as this one exist, and hopefully someone can lead me in the right direction.

Thank You,
Brian

 

Check the voltage at the alt. It may have been replaced at one time and had the wrong one installed. Could also be the voltage regulator but I think that would be part of the alternator in your truck. Worst case find a local boat/auto eletrical shop around the house, chances are they'll be cheaper, faster, and better than the dealer to find/fix the problem.

 

I had a battery go bad but didn't change it out right away.I barely got the truck started one morning and after a half hour of driving had smoke coming from under the hood and the BAT guage do some wild things .
Ended up replacing the battery and alternator. The new alt had a tag with big bold lettering that stated :DO NOT CONNECT ALTERNATOR TO A DISCHARGED BATTERY.
I did and the alternator immediately started overchageing (about 17 volts) and began to 'cook' the battery.The bad battery killed the alternator.

15.4 volts is too high.It should not be over 14.0

 

The transistor in the voltage regulator shorts (collector-emitter) which causes the alternator to run wide open.

 

was the truck hit in the frount

 

Yes, It was hit in the front. Are you a psychic?

I'm going to take the alternator to be tested and go from there.

The timely responses to my cry for help have been amazing. Thanks so much.

 

Was it just hit in the front and thats wahts causing these problems or did these problems just start out of the blue?

 

check the wiring frome the head light tot he fuse box and do the same thing with the air bage censer

 

i hade the sam thig with my focus and i re wierd it and i fix it

 

Not sure because I didnt notice a problem until we finally got the headlights installed and a couple new headlight plugs wired on. I will definitely re-check the wiring up front.

 

Can you direct me towards the air bag sensor. No idea what it looks like. The airbags never deployed if that means anything.