Charging Light Warning Ideas

G-RELL

FULLY DIPPED LS
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So this has been going on for awhile. A few times a day, my battery light and check charging message will come up...honestly, It's been doing it for years. I always thought it was failing alternator or battery, and have been waiting to come out to a dead car at some point.... But to this date nothing! I have replaced the battery (with a motorcraft from the dealer), but other then that, it runs and charges fine. my system is setup for running around 800rms but usually dont have it that loud... but the warning started long before i put the system in. I installed a voltage gauge with the system and run 13.5V to 14.0 constantly. maybe a drop here and there at a light and the sub hitting, but never a constant drop... and this usually never triggers the warning... I'll get more under acceleration, then at a stop!

The light will come on at any point, there is no pattern to when it goes off. cruising on the highway, under acceleration, sitting while running... it will go off at any time, any gear, any RPM, and any voltage my gauge says...

Someone (please) give me a list of things to check..

The battery is a new and the alt (as far as i know) is original.
 
Generally, the light only indicates alternator problems, not battery problems. (There are rare exceptions...)
I think that the algorithm to turn the light on is based on the alternator being unable to keep up with demand without going well past the normal operating range.

Normally, my first suspect with alternators is worn out brushes. However, I would be surprised if they could be worn enough to trigger the light, but good enough to hold out for years before full failure. Maybe you have a loose wire somewhere between the alternator and the PCM or between the alternator and the starter?
 
My guess is loose wire. But if it happens when sitting idle also, I don't know for sure.
 
Ill climb under and start poking around... I also thought it would have failed by now if it was a declining Alt. I'm assuming its just a dummy light, and that there is no actual code when triggered?
 
I don't mean to jack your thread sir, but I have a similar issue?¿?¿ The other day when driving my head unit displayed a message I've never seen before it said "battery critically low," and I ignored it. Yesterday the head unit completely shut off randomly on its own and would not turn back on until I turned the car off then on. I checked the owners manual for the head unit and it mentions no battery or battery warnings. Possible indication that maybe the car battery is on it's way out? I also run a serious amount of sound equipment like you do Rell and have been for years. No other funky things electronically going on.
 
Ill climb under and start poking around... I also thought it would have failed by now if it was a declining Alt. I'm assuming its just a dummy light, and that there is no actual code when triggered?

A Ford specific scanner might pick up something. If nothing else, it could tell you how hard the PCM thinks the alternator is working.
 
Thanks Joe / Guys

I don't mean to jack your thread sir, but I have a similar issue?¿?¿ The other day when driving my head unit displayed a message I've never seen before it said "battery critically low," and I ignored it. Yesterday the head unit completely shut off randomly on its own and would not turn back on until I turned the car off then on. I checked the owners manual for the head unit and it mentions no battery or battery warnings. Possible indication that maybe the car battery is on it's way out? I also run a serious amount of sound equipment like you do Rell and have been for years. No other funky things electronically going on.

If the car is operating fine, I'd put my money on a failing head unit, or bad HU wiring connection
 
Hope the HU isn't failing, it has given me no problems whatsoever at any time up until now. I guess I'll wait to see if it happens again. Thanks.
 
Welllll........

I had a BEL radar detector years ago and it displayed a similar message; something like "low battery voltage". I turned the detector back off and on and the warning disappeared, only to return a short time later. I ignored it and continued on to get my daughter from school. I shouldn't have been surprised, but when it was time to leave I had............... You guessed it............. a dead battery! I got an AAA jump, but the car officially died a mile or so down the road. My terminal alternator also took out my battery.

I assume an aftermarket HU? I'll bet your system has strained the alternator to failure.
 
may be a good idea to through a volt meter on the car for a little while... see what its doing while driving
 
Yeah it's a pioneer with navigation aftermarket HU, I've been using it for years no issues up until this week. I think I have a volt meter somewhere if not I'll see if I can pick one up and see what's going on. The car itself should give me an indication of a failing alternator/battery, Check charging system warning I assume?
 
Yeah it's a pioneer with navigation aftermarket HU, I've been using it for years no issues up until this week. I think I have a volt meter somewhere if not I'll see if I can pick one up and see what's going on. The car itself should give me an indication of a failing alternator/battery, Check charging system warning I assume?

My V6 didn't. I know, no message center, but the car gave no indication whatsoever the alternator was dying. It just gave up the ghost one day. My money is on the alternator.

WAIT!!!! My wife's '06 also failed even though the message center said "charging system OK." Just check out how many volts the alternator is charging at the battery. My wife's LS was charging only ~13V, not the nominal 14.5V.
 
OK, ready for this one? I tried searching and nothing came up... you guys are going to assume I'm retarded and that's ok. I always drive with the auto lamp on and with the fog light switch "pulled" so it's always on auto as well.... However, I noticed over the last few days that the fog light auto keeps clicking back in by itself? Last couple of times I thought "maybe I pushed it in by accident" but last night I was mindful of it and noticed it happened. Is this another sign that the battery/alternator is failing? I've come to the conclusion that the car is genuinely haunted.
 
The fog light switch (pull out) is purely mechanical. Either someone is bumping it, someone is turning the lights off and back to auto, or the switch is mechanically defective. Do note that you have to push the switch back in to be able to rotate it to off, parking, or manual on.
 
Yeah I never turn it off, I always leave it set to auto (all the way left with the fog light pulled out) and it remains all the way left (auto) but after I turn off the car and come back to it the fog light is pushed in (off). I never turn set it to off or on.
 
sounds like
ghost_dad_1990_taking_the_car_part_2_zps4e666a20.gif




...anybody?
 
Hahhaa I was joking around with Mlara last night and he said his radio is haunted as the volume randomly increases and decreases on it's own!
 
Hahhaa I was joking around with Mlara last night and he said his radio is haunted as the volume randomly increases and decreases on it's own!

Either a clockspring fault or an internal issue (probably the rotatory encoder) with the headunit.
 
I guess as long as the headlight switch works I'll just keep pulling it back to auto for now... until it fails completely.
 

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