x2nervisx

Ok so I have an 83 944. It starts up fine and stays running until the battery drains. For some reason the battery is not charging.

What I've done so far:

- Cleaned the grounds with my dremel tool in the front passenger and driver's side headlight area.
- Replaced the negative battery cable with a brand new one and also sanded down the contact points.
- Replaced the cable that grounds the chassis to the rear of the engine block.
- I sanded down the contacts on the alternator AND the starter.
- The battery light DOES illuminate and stays on the whole time.
-I've already replaced my alternator with another used one and a NEW voltage regulator and had that bench tested at an auto parts store and it passed all tests. I've actually tried 3 different used alternators with the same results.


With all that done, I still get 12.3 volts when i read across the battery and when I put my voltmeter directly to the alternator, I get the same readings. Increased RPMs do not help. What else should I be looking for? I'm at a loss right now and this is the only thing holding me back from restoring my 944. HELP!

Rock

You've already covered mostly everything. Either you have a short (doesn't sound very likely as the battery light stays on the whole time)


OR

There is possibly a broken point somewhere with the wiring from your alternator. Have you tried checking to make sure that everything that comes off of the alternator is connected correctly and isnt broken?

North Coast Cab

What do you mean by battery light?
The alternator light on the dash should light when the ignition is turned on but go out once running. If it is staying on it is because the alternator is not charging thus allowing the light to go to ground and illuminate since it receives power all the time.

x2nervisx

the alternator/battery light on my dash illuminates when i start the car and stays on while the engine is running.

931guru

As explained in another thread, bad alternator.

x2nervisx

The alternator on the car now is the one I just had bench tested at pep boys.

The test results are as follows:

lamp/diode trio - Passed
regulator test - passed
rectifier test - passed

battery volts:
Low - 13.50
Actual - 14.17
High - 15.40

Rock

Your problem is coming from the alternator somewhere. If the alternator is good, check the wiring harness that comes off of it to ensure that it is correctly connected and not damaged.

Yarf

Make sure there are good connections on the alternator cable from the alternator to the starter
http://www.pelicanparts.com/944/elec...944_84_1_1.jpg

mazdaverx7

have you tested the battery yet?

x2nervisx

Battery is good. After doing some research, could the factory alarm be preventing the alternator from charging? I just noticed that when I turn the key on, i can hear the factory alarm box clicking (the horns don't work so i assume the clicking would mean the horns going off). I don't have a key for the alarm and i also noticed that the wiring was disconnected from the key hole for the alarm anyway. I've read in somebody else's thread that he was able to start his car with his alarm brain removed but it prevented the alternator from charging his battery. I've already researched how to disable the factory alarm but every single post i've read deals with the later style alarm. I haven't found anyone that has disable the factory alarm in an early car. I've tried the clarks garage method but the alarm relay still clicks when i turn the car on. Is there a definitive way to disable the alarm on an early car?

pnbell

Does the car die while Driving?

x2nervisx

yes it does

pnbell

ok, well that certainly seems like an alternator issue then... How about the Belt; is it tight enough?

My belt was loose once, and it caused the voltage to drop...

bertelli_1

You have a problem with the low current cable from the alternator - this is a small blue or black cable. Certainly on a late car this does indeed run via the alarm box, however I'm not sure about the early cars. You need a wiring diagram & then check this wire for continuity from the alt to every place it goes.

joes

The alternator has to have a "tickle" from some source to start charging or to better say turn it on. There should be one of the wires that has power on when the key is on/ no power when key is off.By looking at the diagrams it's D+