Bad battery or bad alternator?
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Joined: Nov 2001
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Bad battery or bad alternator? The problem is like this. At cold start the voltage is 12.9-13.0. When I start driving my car the voltage starts climbing gradually & it takes 20 minutes to reach 14-14.2v.
Anyone know what would cause that?
TIA <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />
Anyone know what would cause that?
TIA <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />
Re: Bad battery or bad alternator? The reason your voltage is low on cold starts is because your air pump is running, which drains power....
If you don't notice any dimming of lights, or any dead batteries then you do not have any charging problems. I would not pay to much attention to your guage, they aren't that accurate..
Josh
If you don't notice any dimming of lights, or any dead batteries then you do not have any charging problems. I would not pay to much attention to your guage, they aren't that accurate..
Josh
Re: Bad battery or bad alternator? start you car and disconnect your battery, if its the alternator it will go dead. If its the batter it will keep rnning. <img border="0" alt="[cheers]" title="" src="graemlins/gr_cheers.gif" />
Re: Bad battery or bad alternator? This is not good advice for cars that
have a lot of electronics (especially
ones that need those electonics to
run). The battery is the only thing
that holds down the system voltage
during load dump events (like when
your A/C compressor shuts off, or
something else ceases drawing current).
Without it, you can see voltage spikes
that are very large. This can hurt.
have a lot of electronics (especially
ones that need those electonics to
run). The battery is the only thing
that holds down the system voltage
during load dump events (like when
your A/C compressor shuts off, or
something else ceases drawing current).
Without it, you can see voltage spikes
that are very large. This can hurt.
