Alternator or?

Drove my 93 miata about 130 miles and stopped to take a break and car battery was dead. NOTHING. Had it towed mechanic said battery recharged ,alternator checked ok. Started and ran fine for about 130 miles and did it again. Battery lifeless. Racharged and all was well. Took car to starter shop and mechanic checked it and said all was fine. Running has 13.99 volts . Put a load on it and it holds fine at 13. NOW. Some say get a new battery. Others say regulator in Alternator is overheating and tripping. Time spent charging battery cools regulator and it starts ok. Any ideas? Thanks in advance Earl in North Carolina.

The alternator does appear to be the problem. I assume the battery warning light isn’t turning on while you are on the road. It would be good if you check out the wiring to the alternator while the system is hot and running to make sure there isn’t a problem there. Replacing the alternator will most likely clear this problem.

I have 2004 Kia Amanti and have replaced original and 2 more batteries since. Dealer has checked for leakages,found none and my batteries will not recharge…consider yourself lucky?

More info is needed. Automatic or manual transmission? Any starter solenoid “click” sound? Do the dashboard warning lights illuminate when the key is turned to the RUN position? Headlights operative and do they dim when the starter is activated?

Get yourself a $20 digital voltmeter. Drive 100 miles. Check the battery voltage while the engine idles. Should be 14V +/- 0.5V. If the voltage is OK then the battery has a cracked internal connection. Breaks aloose when the battery gets hot. The alternator keeps the voltage up and running. I’ve seen this before. Battery cools off a little and it seems fine. Alternator/regulator failure usually turns on a light on the dashboard.

124k miles 5 speed. Nothing but dead sound no noise when trying to restart . No warning lights . Lights do come on when switch is on with good battery. But when it wouldnt restart no lights of any kind no click. ZIP .

I think you need a new battery-not holding a charge for very long.

I have had this car for 3000 miles and this is the first problem with it. The battery is only 2 years old. Could it go out thhis soon?

It is possible that the battery is bad but it is a good sign that it takes a charge. I suggest you replace the alternator if the battery checks ok after doing a load test on it.

My first suspects would be a faulty ignition switch (electrical part) or fusible link problem.

In regards to the fusible links, I believe this vehicle uses the so-called PAL fuses which are a small plastic box with a soldered contact inside. Sometimes the solder will melt due to age/heat and contact may be broken inside. This problem may occur on an intermittent basis.

The fuse/relay box should be marked and you should inspect the high amperage ones that provide most power to the vehicle.
The clear plastic cover can be popped off and if the link/fuse/whatever you want to call it appears to have solder balled up on the center of the copper contact it’s entirely possible the link is failing.

When hot it may develop an open circuit (bad) and after a few seconds of cooling may become closed again (good). This was also a problem in the old days when glass fuses with soldered end caps were used.
Hope that helps.

Yes. That’s why they have warranties. I had to replace the battery in the wife’s truck in 2-1/2 years after battery stranded us. They bench-tested it, and swapped it for new under warranty.

Even if the battery itself was perfectly good when these troubles started, running it completely flat several times has probably damaged it. If the alternator is failing to charge, and the ignition is supported solely by the battery, I kind of doubt you’d get 130 miles (but maybe…). At a minimum you’re probably looking at a replacement battery and maybe a replacement alternator and/or associated regulators.

Oops, already said the battery is 2 years old. Statement about old battery removed.

I bought one of those voltmeters you plug into your lighter socket and all day it has been reading 14.99-15.1 volts. When I said I got 130 miles I am saying that is as far as I got . At 130 miles I shut it off an d no restart. So the systems started failing before 130 miles.My guess is about 90-100 because that is when the radio stopped working. I then drove to a rest stop and then the no start happened. I am going out tomorrow to get a battery and see what happens.

If it really is 15V (should verify with a good meter), then that is a little too high. Check the regulator.

Drove it today and voltmeter reads 14.4-15.1. Average was 14.4 all day. That was with plug in voltmeter. Checked with automotive meter at auto shop.Is this indication of bad alternator internal regulator?

Yes, but make sure the wiring to the alternator is good first.

installed new battery today voltage now 14.0-.3 . Is this ok or a bit too high? this is with a load of headlights and radio. Is a alternator still needed?

Isn’t this voltmeter reading little too high? I have a voltmeter (I mean not a good one, but I think it is fairly accurate) plugged in a 2004 Hyundai Accent and it never goes above 14.2V.

My problem is in this thread:

The voltage is good. You need to concerned when the voltage goes over 15 volts.