Lights Pulsate......Alternator failing????
#1
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The headlights and insturment lights pulsate worse upon start-up and I do see it when Im driving but it seems worse upon start-up.
Is this a sign that my alternator is failing?
Thanks
Steve O
Is this a sign that my alternator is failing?
Thanks
Steve O
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Holly crap there are alot of people with the same problem lol. Im not really getting what you mean by pulsating?? Also you might wanna check grounds or something, it doesnt seem like an alternator problem. You should check the alternator just in case though.
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#8
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If it's been going on for a long time alternator is probably good, see if it's charging at least 13.8V at the battery terminals. Only time I've really noticed my lights/inst panel lights/radio lights flicker at the same time is when the air pump cycles on a cold start, it draws a lot of current.
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Nope neither one.
No surging or anything like that. It usually only does it when the cars cold. Usually after work, 8 hours of sitting or in the morning.
No surging or anything like that. It usually only does it when the cars cold. Usually after work, 8 hours of sitting or in the morning.
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Mine did it really bad at one point, it was caused by the aux terminal port near the fuse boxes. That nut on the positive post was loose, and that did it. Hasn't done it since then. Check all of your battery connections. These cars tend to rattle smaller stuff loose, and it's not unlikely that something came loose on you
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I would put a multimeter on the battery and measure the voltage before and after starting. I would use a analog meter so you can see how much fluctuation in voltage you are getting. Most digital meters are not fast enough to see the fluctuations. Measure the voltage at the battery and alternator while running. There shouldn't be more than a few tenths of a volt difference between the two. When you measure the alternator voltage, use the alternators chassis for ground and then try the battery's ground. If you see a big difference between the two, you have a battery ground problem. After this, if all looks good so far, unplug a headlight and turn them on and see how much difference you get in the voltage again. If there is a big difference, again keep the positive lead in the headlight circuit and move your ground lead to the battery, or alternator chassis. If you see the voltage come up a bunch, you have a grounding issue in your headlight circuit. If the voltage doesn't come up, but it is low to the headlight circuit, there could be too much resistance in the headlight switch circuit, or too much voltage loss between the battery and headlight switch. I know the corvettes have a common problem with the grounds getting oxidized or corroded and make the computers go nuts. The remedy for that is to take the ground connectors apart and clean them or cut the plastic connector off and put one large ring terminal on the wires, properly crimp it and re-ground everything under the hood.
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Wow,I'm amazed at how many people have this problem as well...
I also have NO systems (audio),underdrives...etc..No lopey cam...nothing out of the oridinary.
Mine is very intermittant and actually seems to happen once I have been driving around a bit.
You can see a very slight pulsating of the lights in the guages,radio display and the slightest of twitches with the factory volt guage.
You can see the problem better at night if you turn on your reciew mirror lights (map lights) while idling.Then sometimes its not doing it at all...
That "intermittant" problem to me indicates that there has got to be something "loose".
BTW mine just started a couple of days ago...
I also have NO systems (audio),underdrives...etc..No lopey cam...nothing out of the oridinary.
Mine is very intermittant and actually seems to happen once I have been driving around a bit.
You can see a very slight pulsating of the lights in the guages,radio display and the slightest of twitches with the factory volt guage.
You can see the problem better at night if you turn on your reciew mirror lights (map lights) while idling.Then sometimes its not doing it at all...
That "intermittant" problem to me indicates that there has got to be something "loose".
BTW mine just started a couple of days ago...