Alternators
Car Batteries
Timing Belts and Chains

Why would the alternator stop charging at low rpm and or with multiple accessories running?

969798

Top Answer
User Avatar
Wiki User
2004-07-01 13:54:40
2004-07-01 13:54:40

Hey Chris==Make sure the belt is tight. If it is, it can be problems inside. GoodluckJoe

1
๐Ÿ™
0
๐Ÿคจ
0
๐Ÿ˜ฎ
0
๐Ÿ˜‚
0

Related Questions

User Avatar

Spark Plugs do not affect your alternator. As long as your engine is running then it should be charging unless your alternator is bad

User Avatar

The charging system is the alternator which is on and functioning anytime the engine is running. If not, then you have a problem with the alternator.

User Avatar

If it is running on the battery only then that means the alternator is not charging the battery.

User Avatar

No. The alternator has to be turning to produce the charging voltage. It only turns when the engine is running.

User Avatar

Yes, a loose battery cable will prevent the alternator from charging the battery. The drain on the battery is not caused by the engine not running unless an accessory is left on. Most likely, the drain is caused by accessories (radio, lights, etc) while the engine is running due to the battery not receiving its charge from the alternator and then not having enough charge left to start the engine.

User Avatar

Yes, because a bad coil will not allow the engine to run. But if the engine is running then the coil has nothing to do with the alternator charging the battery.

User Avatar

If the alternator is not producing 13.5 to 15.5 volts it is defective and needs replacing.

User Avatar

bad alternator ? its not charging the battery

User Avatar

The battery light indicates the system is not charging. Have the charging system checked. If the alternator is not charging, the engine will quit running and leave you stranded.

User Avatar

A quick way to check alternator on any vehicle is while engine is running,carefully touch a screwdriver to the spinning part (armature) of the alternator. If it is magnatized, it is charging. If not then alternator is not charging. The voltage regulator (the thingy that tell the alternator to charge) is built into the alternator. Replace the whole thing with a rebuilt unit.

User Avatar

your alternator charges the battery while the car is running. The alternator actually puts out a higher voltage than 14 volts while it is running, but it is reduced by a voltage regulator (most of which are already built into the alternator housing), to prevent damage and premature death of the vehicles battery. While your car is not running, the alternator is not charging the battery, and the 13.5 volt reading you get is just the measurement of the voltage the battery is holding at that given point.

User Avatar

If you can jump it and get it running again, drive it for a few miles and then it dies again, it is the alternator. Buy a new alternator and it will fix the problem assuming you do not have bad connections "wires" in your charging system "your alternator and your battery".

User Avatar

No , for the battery to be charged the engine must be running . This means that your alternator , if it's functioning properly , is charging the car's battery as the engine is on/running .

User Avatar

Check the voltage at the battery with the engine running. It should read from 13.5 volts to 16 volts. If it reads lower than 13.5 volts the alternator is defective.

User Avatar

You have a problem with the charging system. More than likely the alternator has failed.

User Avatar

with the car running disconnect the negative terminal from the battery if engine dies alternator is no good

User Avatar

It means your alternator (generator) is not charging the battery while the engine is running.

User Avatar

As long as the alternator works and your charging system is correct, the new battery will start your truck and keep it running.

User Avatar

Check the gauges, if the car is equipped with them. If you have a volt/amp gauge, it will read the alternator output for you. Turn on the blower fan for the AC or Heater, the headlamps, and any other accessories that put a strain on the alternator, and watch the gauge to see if it decreases voltage or amperage. As a rule, if the voltmeter is higher when the engine is running then when the engine is not, you can confidently assume that the alternator is charging. Check it at the battery with the engine running. It will show at least 13.5 volts if the alternator is good. If these values decrease when you turn on electrical accessories, the alternator may be weak. Listen to the alternator while the engine is running. If there is a problem with the bearings you may hear a squealing sound coming from the front of the car, which becomes louder with more electrical accessories using power at the same time. Feel the alternator after the engine has run a few minutes and you turn the engine off. If it is very hot, you may have wear to the bearings or the insulation on the copper windings may be breaking down, an indication the part may fail soon. To actually measure the charging current on a cheap modern digital volt meter: Set meter to most accurate voltage range, with the engine off measure the voltage between chassis and chassis connection at the battery, this should be nearly 0 volts, now turn the headlights on, the headflights will draw about 10 Amps and the volts drop across battery earth to chassis will show about 50 millivolts dependent on the resistance of the earth strap. Remember 50mV is proportional to 10 Amps. Turn the headlights off and start the engine, the meter will show the charging current and this will be in the opposite polarity as the current will flow in the opposite (charging) direction. for example if the meter shows 100mV the alternator will be charging at 20A. turn the headlights on and you will see the charging current to the battery reduce as half the alternator current goes into the lights.

User Avatar

best way to tell if the alternator is charging is to unhook the battery with the engine running, if it shuts off then you know you have a bad alternator, i wouldn't recommend this with newer vehicles due to the fact you could hurt the computer but an 89 i wouldn't worry about that so much, good luck!

User Avatar

Alternator not charging battery sufficiently? Check with a voltmeter: A fully charged battery should read approx. 12.8 volts without engine running. With engine running should read approx. 13.8-14.2 volts

User Avatar

Connect a voltmeter across the battery terminals without engine running reading should be around 12.8 With engine running reading should be 13.8-14.2 if you are getting these numbers alternator is charging battery

User Avatar

Check output of the alternator--With voltmeter With engine running readings should be 13.8-14.2 volts lower means probably a bad alternator

User Avatar

low charge, rough idle, dimmed lights. With the vehicle running and headlights on or wipers on the alternator should be charging around 15v 15.5v


Copyright ยฉ 2020 Multiply Media, LLC. All Rights Reserved. The material on this site can not be reproduced, distributed, transmitted, cached or otherwise used, except with prior written permission of Multiply.