2014 F150 Electrical Issues
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2014 F150 Electrical Issues
I have a 2014 F 150 5.0 STX, lately i have been having some weird electrical issues. last week i started to notice my headlights dimming when i turn the wheel, and when I'm sitting at a stop light at idle with the ac on the truck will go below 500 rpm when the ac cuts on. I took a 3 hour round trip to go fishing this past weekend, and when i was on the way back the battery light came on for about 3 seconds and went off. was confused so went to auto zone and had it tested. The alternator was shown sending 15.2 volts to the battery. bought a re-manufactured one from them for $350 and had it installed for $160, but the truck is still acting the same way. Lights still dim, still idles funny, and positive side is still hot, still melting rubber cover. Took it to Advanced, was showing 15.3 voltz and 15.98 under load, went to auto zone and Oreilly's both showed it at 14.5. Battery also checked out good at all 3 locations. I'm at a loss right now. I cannot think of anything. I called my dad, he did some research and thinks that since i didst reset the battery monitoring system when i switched batteries ( about 2 months ago) that may be the problem. I dont see how that would effect how the truck idles and the lights dimming. I'm open to any opinions. I am planning on trying to reset the BMS tomorrow, but i don't have high hopes. I'm really frustrated as that i just paid off the truck the day before these issues started (at 78,000 miles now) first real problem with the truck, but seems to be a big one. I am nervous there are deeper electrical issues. Thanks in advance for any help.
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I did not replace the voltage regulator. I looked into that earlier, but cannot find any voltage regulators for my year and model which leads me to believe it is a part of the alternator, but i could be mistaken.
Hi, the positive side of what??? is hot and melting the cover. This sounds like you just have poor and or dirty battery cables.
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From: Chico, Ca.
The regulator is integral to the alternator. I'd be following the leads off the positive terminal to their various destinations. I suspect you have a primary lead thats chafed through and experiencing intermittent shorting.
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I looked at all the cords coming off of the positive side of the battery terminal. Could not find where anything was rubbing that might cause a fault. I pulled the alternator 10 amp fuse also just to be sure and it is fine. I’ve got a list of other fuses to check to see if they may be causing problems. I do have some aftermarket lights, all leds so shouldnt draw much, but will disconnect all of them today. Also will try and clean battery connections even though they seem fine. I’m starting to wonder if maybe a PCM relay is faulty and causing the truck to run rough and use engine power to run headlights/ AC blower.
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So took the truck in to get diagnosed by a local shop we take our fleet vehicles too. The positive side was a little lose. He fixed that and got the alternator down to 14.8-14.7. Truck is still dipping at idle. I had the guy come watch it and he said since the alternator I have is remanufacrured that is most likely how it’s just going to be from now on. I’m not really sure what to think of that answer. As long as the alternator isn’t over charging anymore I’m not nervous about driving it. I am thinking that the idle may have something to do with a dirty MAF sensor, going to clean that today and get a new air filter since I didn’t replace it last oil change.
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Exactly how many (and what) lights do you have added to the truck? Heavier draw could cause some issues. "LED" doesn't mean zero electricity, esp if you are loaded with big ones.
There is a TSB for upgrading fuse 27 (fuel pump), look into it regardless of whether it seems to be an issue.
How many miles on your spark plugs?
There is a TSB for upgrading fuse 27 (fuel pump), look into it regardless of whether it seems to be an issue.
How many miles on your spark plugs?
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I have after market LED headlights and taillights after market led cube fog lights and led cube reverse lights. All these items have been on the truck for at least a year.
7 out of 8 spark plugs are original with 78000 miles on the. Had to change cylinder #2 about 20000 miles ago because of a miss fire code. I will look into the tsb on fuse 27.
7 out of 8 spark plugs are original with 78000 miles on the. Had to change cylinder #2 about 20000 miles ago because of a miss fire code. I will look into the tsb on fuse 27.