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1992 LX Hatchback won't charge battery

1799 Views 11 Replies 5 Participants Last post by  TOM RENZO
So I was driving home last night when everything got dim and the car finally quit.
I had someone come give me a jump, but it would only drive about a mile before quitting again. we jumped it, drove a mile, jumped it, drove a mile all the way home.
I took the battery and the alternator out and brought them to both Advance Auto and Auto Zone (for good measure) and both places said they checked out fine. (this included the voltage regulator on the alternator)
Any insight on what could be going on here?
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Install the battery and alt then jump the car and get it running with a good battery or charge yours. Then check the charging voltage across the battery at 1300 RPM'S. The charge voltage should be 14-14.7 VOLTS. If not the alternator is shot or the wiring in the car needs attention. Do this and post back Peace Tom:bigthumbsup:bigthumbsup:bigthumbsup
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Got the alternator and battery reattached.
Checked the voltage of the full battery with the car not running and got 12.59 volts. Turning on the car and idling at 1200-1300 RPM yielded no change. It did not go up to 14-14.7 volts.
I disconnected the battery cables and cleaned them up as much as possible and still no change.
The alternator checked out fine at two places, so I can't imagine that's the issue.
Should I just suck it up and bring it into the shop?
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so after reading around on the internet, i read that having the bench test done at autozone is worthless if the alternator is disconnected from the car since it's not under load.
is this true? should i bring it to the local shop (autozone is an hour drive) and pay $30 to have it hooked up to test the alternator?
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id reccomend the 3g alternator upgrade, relatively easy and fairly cheap if you can get to a junkyard, the oe alt is only 75 amp at best, with the age and mileage might be less. lots of links on here for the job.. hardest part is grinding the bracket. also check your grounds, not just at the battery but also down under the engine, ground wire should be on a bolt at the bottom of the alt bracket and also check your body to engine strap, its on the firewall behind the head and goes from the firewall to a head bolt.
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i keep reading about a possible bad fusible link. can anyone assist me on where that is? maybe a picture?
thank you...
Fuse links are at the starter solenoid. Give them all a yank in the middle of them. If they come apart they are shot. But get out your test light and check to see if battery is at the heavy wire terminals of the alt. Then concentrate on the KEY battery from the cab. That is the one that feeds the ALT LIGHT. Normally bench testing is a joke. But some testers do a good job even if they are not loaded down. But you can full field the alt by grounding the appropriate lug on the back of the regulator with the engine running. This will test the alt void of the regulator. But first check the wiring for battery's as i explained Peace Tom :bigthumbsup:bigthumbsup:bigthumbsup
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i found the fuse link thanks to this diagram. i yanked and it seemed fine. i used an ohmmeter and it tested normal too..
the wife is on her way home with an alternator, so we're going to throw that in and see if it solves it. if not, we'll return it.
Tom, don't forget that the main output line from the back of the alternator over to the starter solenoid is a fusible link. In fact it's two links parallel. I didn't know this until I did the 3g conversion and replaced them with a single heavy gauge wire and a big fuse. The alternator could be fine as well as the battery, but if there's no path from the alt to the battery, then it won't charge.

Easy way to check this is to disconnect the battery, set your voltmeter to continuity and put one lead on the lug on the back of the alternator and the other on the side of the solenoid that has the positive battery cable. No continuity means blown fusible links.
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Easy way to check this is to disconnect the battery, set your voltmeter to continuity and put one lead on the lug on the back of the alternator and the other on the side of the solenoid that has the positive battery cable. No continuity means blown fusible links.
can you clarify what you mean by the "the lug on the back of the alternator"... just for a newbie's sake. i don't want to put it in the wrong place and find no continuity and make a false diagnosis (my alternator has two plugs that go into it, not bolted on wires... if that makes a difference)
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the long plug on the alternator with 2 black and orange wires in it, they end up tieing together at the fusable link at the solinoid on the fender. also let me add if the "batt" light bulb is blown it will not charge, it "turn's on " the alternator to make it charge.
Once again check the BATTERY at the alternator with a test light. The 2 heavy ones will have battery all the time and light the test light. This will confirm the ALT has a path to the battery. You can also key the car on and see if the ALT light comes on. If in fact you have a light and not s gauge. I think you have a light if i am not mistaken. AQlso check for battery at the YELLOW WHITE WIRE it feeds battery to the regulator. It should have full battery even with the car off. It is fed by another fuse link at the solenoid. So you should have 3 FULL BATTERY supplies to the alt and one that lights the alt lamp. If in fact the alt light does not come on. Use a test light to probe the wire key the car and see if the ALT LIGHT IN THE DASH GLOWS. If it does the alt light circuit is GOOD. By the way the alt lead to the alt light is Light Green Red

Hay how goes it BIG C. Been missing your posts good to hear from you My brother!!! Peace Tom:bigthumbsup:bigthumbsup:bigthumbsup
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