Ok, I just got a new battery and coil ignition bwd.I also had my alternator re-built about 2 weeks ago,but my battery light still pops on when i turn the headlights on!my belts seem to be tight enuf. is it a problem that im just running off of the 2 main belts instead of all 3 or 4? the car is an 86 chrysler fifth avenue!

Have the Alternator tested and if that is ok have the battery tested for a parasitic voltage draw.

think u hav a bad cable from the alternator to the batt--they wear and gain resistence eating up alternators--its the red cable used to charge batt--some mechaanics just add anothr wire beside the old and it works--hav a honest guy test the old wire

Well I was going to ask if you have checked the alternator output, but the part about the ignition switch makes me wonder if the switch is failing. It could be damaged internally and not up to the task of carrying voltage when everything is turned on.
I would still check alternator output at the alternator and at the battery.
You should have 14 volts at idle with all accessories off.

Hi

Yes it sounds like the alternator voltage regulator is wearing down and needs to be changed or replaced.

If you can get your hands on a 12 volt multimeter, turn the setting to 20 dc and place the negative wire on the negative battery post and the positive wire on the positive battery post.


The battery with motor off should be 12.6 volts and higher, start the the car the read out should be 14.,2 or higher.


You can turn the lights and heater on to see if the alternator can cope with the load.


if read out is less then you need to change or replace it.

Cheers

Did you check primary voltage to ignition coil? red wire with lite green tracer, use a test lite to check voltage, goes hot with key on, circuit is fuse protected.

Do you own or have access to a voltmeter? If so when car is running you should have a range of 12.6 volts to 14.8 at the battery cables.
If not jump start car and run it to local Autozone, Advance, etc parts store and the offer free testing on the car.

Also, if you've been driving for last two weeks on bad alternator, you might have damaged new battery.

replace the charging relay

Make sure the battery is good and fully charged . You will get the code if the battery is bad on the transmission.Check the ground wire from the engine to the frame of car. Must have a good one. Check to see if the battery cable is getting hot. The gauge inside the car could also be bad. A few things you should look at

If your lumina has a Pass II key, it may well be the ignition lock cylinder on the steering column. The car key has a resistor staked on the sides of it which is read by the theft deterent module. The theft deterent module issues a command to the ignition relay and the fuel injectors when it reads a correct resistance from the key. If the lock cylinder is damage( broken wire) ect. the theft deterent module will not be able to read the key. Unfortunately, if you have a Lumina with a solid shroud around the steering column, the dealer will charge you $700-$1200 to replace the cylinder.
Good luck

If your is exhibiting the same signs as a dead battery it really sounds like your alternator is bad. If you are handy, you can remove the alternator and take it to an autoparts store like autozone and they will test it for you. This is not a hard job to do, usually 2 electrical connections, 3-5 mounting bolts and you have to pop the belt off. Just reverse it to install a new one. Good luck! - Nick