# Nissan Sentra 94 Battery light problems



## Jessikah (Jun 8, 2013)

I just bought a Nissan Sentra 1994 a few months ago and when I first got it, it was working perfectly fine. As I drove it more problems started slowly happening. First was my electric seat belts and AC/Heater stopping to work completely. I knew it had to be something with my fuses, so I changed them all and the seat belts worked but the AC/heat didn't. Now my car is acting really weird. My brake light and battery light were on at the same time, and as I read on the forums that means there would be an alternator problem. Just to be sure I got both a new battery and a new alternator and replaced the old ones. I also got new lids for the battery terminals (not sure if that's the correct term) because I heard those can get corroded and not be tight enough. After everything had been installed, last night I figured that it would be okay to start up and drive around a bit. The car now runs perfectly fine again but my battery light still continues to be on and it becomes a bright red when I turn on my headlights. I'm scared it might die while I'm on the road somewhere. By the way my heater still isn't working. I'm a girl and I guess I don't know much about cars, I'm hoping someone can give me advice on what to do next or what may be the problem here? Thank you for all your time!!!


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## Centurion (Sep 5, 2002)

Could be a defective alternator. Been there, done that, many times. Oh, and this is with using new alternators, not rebuilt.


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## Jessikah (Jun 8, 2013)

Really?? So should I just buy a new alternator and see if that fixes the problem? I just recently called Auto Zone and they said that a diagnostic wouldn't tell me more about the car than I already know and they also suggested that I have my voltage regulator checked because that's what seems to be the issue. What do you think?? And what is a voltage regulator? Is that all electric work? I mean is it even worth it on this car or would you suggest just getting a new one?
Thank you so much for the reply!


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## smj999smj (Jan 1, 2006)

The voltage regulator is inside the alternator. The battery and brake warning lights on at the same time indicate a charging system issue. It could very well be a faulty alternator, but without doing any testing, who knows? First, the charging system voltage should be checked. A properly operating charging system should be at 13.2-15.0 volts, with and without loads (headlights, A/C, etc.) "on." If the voltage is above that spec, the regulator is faulty and you need a new alternator. If the voltage is below that, the fusible link for the alternator should be checked (it's a wire that runs off of the positive battery cable) and the wire to the "BAT" terminal on back of the alternator should be checked to make sure there is power and there is minimal resistance through the circuit. If that's okay, replace the alternator. There has been a history of problems with aftermarket alternators and starters on Nissans; I recommend using genuine Nissan remans. Since you already replaced the alternator, you should find out if there is any warranty on the part so you don't have to pay for another one. 
As far as fuses, they are either "good" or "bad"; they don't usually cause intermittent issues.


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## b13er (Apr 7, 2010)

Here is that I would have done:

Taken off the alternator.

Take it back to Autozone and have them do the very sophisticated diagnostics test on it, and see if it passes.

Never listen to the people that work there. To diagnose my alternator, one guy who worked there had me check the voltage between an alternator cable and the engine block, without the engine running. Which makes no sense of course, the engine has to be running (NOTE: they have a better testing machine than a voltmeter to check your alternator outside, or you can take it inside to have the best test done to it). He then goes on to tell me he used to work as an auto-mechanic.


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## worthirt (May 21, 2013)

if you are still having the problem, check for a bad ground also. Mine was bad by the battery. Grounding problems can cause all kinds of issues. Don't rule out the alternator problem either.


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## b13er (Apr 7, 2010)

Sound advice worthirt. I grounded my battery in 5 different places when I installed my grounding kit: http://oi44.tinypic.com/htv702.jpg you can see 3 of them there plus the stock ground and then I made a backup "stock ground" lol.

I was just driving last week and both the battery and brake light started blinking. I drove it strait home, left the car running, and put my multimeter ($12 buy one) on the battery and it said 12 volts. Next I tested the alternator leads and they said 12 volts. Got my 5th one at autozone, installed it, checked it, and it said 14.4 volts. Hopefully this one will last longer than 2 months.


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## BeyondBiscuits2 (Jan 18, 2006)

More than likely you got a defective alternator, especially if it was "remanufactured". Having worked in a parts store, as well as a shop, I can tell you remann'd isn't worth the money. Just buy a new one. Most companies that rebuild components don't properly assess their cores. It would take WAY too long for that. They simply fix the most common issues. On starters: the solenoid. On alternators: the diodes. Rarely do they take the time to check the brushes and bearings in an alternator, or the other components in a starter.


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## smj999smj (Jan 1, 2006)

Here's a good example of why I suggest genuine Nissan parts! Save a hundred bucks on an Autozone or Advance Auto Parts reman lifetime alternator and then have to replace it five times! How much money do you really save if you put any value in time and confidence that a part won't fail on you at the least convenient time?


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## BeyondBiscuits2 (Jan 18, 2006)

I personally have had good luck with reman'd parts, but I suppose I am the exception. I've heard horror stories of multiple trips to the parts store, with no end in sight. I should also make a note that remanufactured parts from the dealer are typically much better assessed and repaired. Typically, though, dealers only offer reman'd variants for parts no longer being produced, i.e. distributor on '84-'88 300ZX models.


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## i r teh noobz (Apr 26, 2007)

I usually have good luck with remans, but I have had multiple failures as well. They generally fail within a few minutes if they're no good.


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## smj999smj (Jan 1, 2006)

Nissan has always sold replacement parts like alternators, distributors, starters as "remanufactured," even though in many cases they are brand new parts. I always figured it must have something to do with taxes they pay on them, but I'm not sure. The first time I ever got a Nissan remanufactured part that actually looked like it was remanufactured, rather than brand new, was in the late mid-90s when Nissan had a lot of problems with the 95 Maxima starters cranking the engine too slow and causing flooding issues at startup. The countermeasured the starters to spin the engine faster. It was the first time I ever pulled a Nissan reman starter and could see evidence that the starter had actually been installed on a vehicle previously.


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