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Discussion Starter #1
Hey ,..z fans another z guy ... I’ve been having this on going problem for a while now where the car runs off the battery instead of the alternator.

replaced alternator so alternator is new ,.. no change,.... replaced fuseable links with still no luck... any advice guys ... this is really annoying,.. seeing that if I didn’t have this one problem everything would be fine... car runs a drives fine just keep draining down the battery instead of working off of the alternator
 

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Before you assume the alternator is working properly, test voltage across the battery terminals with the engine running. Should be above 14V.

Alternators, especially from discount stores, can be bad out of the box. I like to have my original one rebuilt if I can find a shop that still does it.
 

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True,.. will try a three Alternator then and give it a shot I believe the second one that I got was a remanufactured and could be faulty
 

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The battery is a brand new battery, when I took the negative lid off and put my meter in series with the circuit I get -7..

And when I run the car and test for the voltage it goes from 13 12 11 10 9 8 7 and so forth and just keeps dropping
 

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Do you mean putting the meter in parallel? In series you're imposing current through the voltmeter circuitry and I don't know what that will do to the analog-to-digital circuitry for the numerical dispaly, but I don't think it's a good result.
 

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The battery is a brand new battery, when I took the negative lid off and put my meter in series with the circuit I get -7..

And when I run the car and test for the voltage it goes from 13 12 11 10 9 8 7 and so forth and just keeps dropping
I don't understand that response, so let me be specific.

Engine off: contact + and - terminals on battery with the + and - probes on a digital multimeter. Do not start the engine, just take a reading. You should get a DC Volt reading above 12V, normally around 12.5V give or take.

Engine running: Start the engine, and right away use the same connections, and check DC voltage for a minute or two. If it constantly varies and consistently shows a reduction in voltage, then your alternator is faulty. An alternator in the older vehicles should provide a constant 14.4V (give or take a couple of tenths) while running.

If you had a newer vehicle such as a Murano or Rogue, then after the engine has been running for a minute or so, because the charging system is more intelligent the voltage would drop as the battery charges up. This is NOT the case for the older vehicles like the Z, they will show a consistent voltage while running.
 

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Is your voltage regulator functioning properly? See the EE section of the FSM to find the diagnostics.
 

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I once had a similar problem with my pickup. All the connections seemed tight, the alternator was working, and the battery was fairly new. If the conditions are right you can get a thin build up on terminal ends that looks like clear lacquer paint. It will stop the charge from getting to your battery. A wire brush may not clean this stuff off, I took a flat blade screw driver to mine and then some emery cloth. It worked like a champ.
 
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