Has me a bit puzzled
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[QUOTE=Jayeffel;6617324]
No, hell no. That would work perfectly. I was under the assumption that it wasn't drivable due to the charging system. If it's drivable, go for it. I'm still betting both will be needing replacement with that much and many draw=downs that have occurred. It's certainly not uncommon.
Now that we have a bunch of ideas, let me add. Both ideas are probably correct. The alternator is probably going bad, thus causing more load on the battery, thus the battery check light. I'm going to bet that if the alternator is bad, the battery is bad now also. One can't keep putting out to cover the difference, so it's probably just both needing replacement now. It isn't uncommon to loose a battery from a bad alternator.
If it was me, I'd take both off and have them bench tested. Go from those results. JMO, of course.[/QUOTE
Would not the test machine at Advance Auto (our others such) telll pretty much the same as removing them and testing separately? I know it seems logical but there may be something to preclude the same results.. At least that should give an indication where to look. Thank you for taking the time to answer.
If it was me, I'd take both off and have them bench tested. Go from those results. JMO, of course.[/QUOTE
Would not the test machine at Advance Auto (our others such) telll pretty much the same as removing them and testing separately? I know it seems logical but there may be something to preclude the same results.. At least that should give an indication where to look. Thank you for taking the time to answer.
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No, the in car test is not as reliable as having each of them tested separately on a bench. I can't even count how many times I've seen either of them test good when in the car, but they were actually bad. When they are in the car and are (half-assedly) working together it can deliver a false reading.
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Most common reason for alternator failure is bad battery.
low battery voltage on dead battery draws too many charge amps, frying the regulator in the alternator, burning out diodes, etc
They are not designed to charge dead batteries. Keep doing it....you replace battery AND alternator
low battery voltage on dead battery draws too many charge amps, frying the regulator in the alternator, burning out diodes, etc
They are not designed to charge dead batteries. Keep doing it....you replace battery AND alternator
Last edited by mbb; Jun 14, 2020 at 02:10 PM.
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I know back when I started driving you could start a vehicle, take the battery out and go about your business- until you turned off the engine. Of course back then a lot of things with vehicles were different-- wing vents in windows, fender shirts, hubcaps, no safety belts (well they were just being introduced). And when you opened the hood you could actually see the engine.
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Jayeffel, I feel your pain. My first car was a '69 Plymouth Fury 1, 225ci slant six. Because those cars could be ordered with as much as a 440ci v-8, I had enough room in the engine bay to climb in and eat my lunch. And the simplicity of working on it - I had to replace the oil pump. It was on the outside of the engine, two bolts to remove. I think it took me an hour and I'm kind of an all thumbs type. Compare that to when the fuel pump went on my '99 F150 4.2l - tank had to be dropped (beyond my skill set) and the new pump cost over $400 - with labour and taxes it cost me just over a g-note. Oh, for the old days.....
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From: KY.
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From: KY.
WRONG! I've had several experiences with this kind of thing lately (ten+ years) and in every case it was a bad battery. Think of it this way, even if you had a completely dead alternator the battery should keep the truck going for for an hour or more but you would see the alternator warning light (or whatever indicator is used in your truck) come on. The fact that the OP isn't getting warning says that the alternator is most likely ok. But a bad battery CAN have a momentary short and that will shutdown some or ALL of the electronics even if the alternator is still working. The older batteries rarely failed in a dead short and when they failed, the alternator could supply enough power to keep all of the electronics and the vehicle running indefinitely. The newer batteries and the newer vehicles simply don't behave like that. Dead shorts are common and also the newer vehicle require considerably more electrical power for things like the Electronic Power Steering, and in addition the computerized controls will not tolerate low voltage the way that older vehicles without computers would. Thanks to the highly computerized controls in today's vehicles ANY glitch in the battery will cause all sorts of bizarre behavior in today's vehicles, if you've been on this or any other automotive forum for very long, you'll have seen dozens of complaints of this and all of them caused by batteries that still worked but were starting to fail.
OP, replace the battery and you should be good to go. It wouldn't hurt to have the alternator tested (they can test it on the vehicle with removing it), but I seriously doubt that you will find anything wrong with it.
OP, replace the battery and you should be good to go. It wouldn't hurt to have the alternator tested (they can test it on the vehicle with removing it), but I seriously doubt that you will find anything wrong with it.
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At night youd be in trouble
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I have a 2000 Lincoln Town Car (with only 22,000 miles on it - It just sits in the garage) that drains the battery. Never could figure it out. I did put a marine deep cycle battery in, as a regular battery is ruined after being completely discharged after so many times. It is a little hard to pinpoint problem and current runs through these vehicles for a few minutes after the vehicle is shut off. Then when the door is opened juice starts flowing again. It takes a week for mine to discharge. Since it is the garage I put a trickle charger on it frequently.