I have 1999 F-150, a few weeks ago my aftermarket radio started acting wierd, and last night while driving home in the rain I lost my electrical power. The dash did seem dim earlier- the wipers slowed WAY down, the air bag light lit up, the radio kept opening and closing itself- then went off, I had no head lights, blinkers, hazards, or speedodometer. I was able to keep driving it home a few miles as the engine seemed to be running ok. Would this be the alternater? ANY advice would be very much apprecitated. Thank you!

 

it could very well be the Alt. if you were using alot of electrical things and the alt is week then it couldn't keep up then you were running off the battery. check it with a multimeter or go to an auto parts store and get it checked. will the truck still start?

 

Yes the truck starts just fine. Will I harm anything else -like a belt or something if I were to drive it to a store to get it checked -and would the turn signals work if the headlights are not on? I don't want to wreck anything else. thank you very much for your help I hope i can get this resolved. I'll wait for your relpy before I take it out on the road.

 

unless the alt is locked up or the bearings have failed and the belt is not making any noise then it will be ok to drive. but if you are running on battery power then eventually it will die.
you can check the basic stuff before you go. check the connections for corrosion and looseness on the battery and relay.
when you have it running now and turn on all the elec things does it still act up or was it only when it was raining.

 

Oh, she stills runs- but loses power fast- didn't make it down the block. So it's probably the alternator. Is that a easy one to replace on these? I know things in the past have turned into nightmares while working on it. Thanks for all your advice- but more question, if you please, as asked above- is it a "easy" repair? And anything we should know in advance? The original alternator must still be in there- the truck has 101,000 miles on her.
Thank you !!!!!!!!!!!!!!!!!!!!!!!!

 

its fairly easy to replace. it just bolts on and has a few connectors to unplug. If you get a Haynes manual it will tell you how to do it with a few pics.
You should still get it tested even if you take it off and then take it in.

good luck.

 

If the truck cranks, then the battery should have enough power to keep the engine running. Correct me if I'm wrong.

 

I'll let you know, probalby this next weekend when i'll have the time and $ to do this. Thank you again for your time and advice. Jeanine

 

Answering the other post for me- after the truck stalled we jumped the battery and it ran for another 5 minutes or so and then we put it on a battery charger to get her into the garage until we can fix it. They said the cranks on the battery was REAL low so I must have been draining it. Thank you eveyone for your help.

 

If the battery is dead, then it's probably the alternator. The local napa here will test alternators for free.

 

Good to know! I'll be sure to get it tested before spending about $160 on one. Thanks again- have a good week!

 

Hope it is an Alternator problem. From the first list, and the addition of rain, I was starting to think GEM

Take a look up under the dash on the drivers side, to see if it is damp back there. If so, you could have a windshiel leak, and the GEM and Fuse panel are getting wet.

The dead battery also leads me to believe that it could be the alternator not charging, but that list got me thinking.

Good luck, let us know what happens with the alternator swap, and battery charging.

 

I think because I had the wipers going along with the lights and radio it just died faster. There have been a few "episodes" of it acting weird a few weeks prior- if a alternator can "slowly' die. The instrument gauge needle would go all the way over and back again and like I said the radio would only work when it was closed (it would normally open to a picture display) and it was working in reverse ( it would open instead of shut when I turned the truck off) we thought the radio was the problem -maybe it's also alternator related. I hope- well not really, I just want the radio to work once the alternator is fixed.
I let you all know once we work on her this weekend.
Thank you all for your time once again..... I REALLY appreciate all the advice.
Jeanine

 

i had similar stuff w windshield leak,no speedometer,radio playing no key in ignition,fan motor running,wipers operating at variable speeds. All occurred right after rains. Was leak in windshield like SSCULLY advised,Gem was just over $500 to diagnose and replace, they didnt catch windshield leak til 2 weeks later and it did it all again,the stealership repaired at their expense this time including windshield leak

 

Truck update. I'm finally able to get to all who helped with my truck. It did end up being the alternator and now is running fine. We had a family emergency at the same time and were going back and forth to the hospital, so that's why I didn't get back to the post sooner.
Thanks again for everyones help and advice on the truck- hopefully it'll be good for awhile now.
Sincerely, Jeanine