Car will not charge battery. HELP!

[Divexxtreme]

I'm having an extremely frustrating charging issue that I can not figure out. My alternator is putting out 13.7-13.8 volts, but my batteries continually die when I drive the car. Autozone tested the electrical system and said that there are no electrical drains (not sure how accurate that test is, though).

This problem has been going on for almost 2 months and I can not figure it out. What I've done so far:

-Replaced stock alternator with remanufactured Bosch units from Pelican Parts TWICE. (first alternator failed Autozone bench test, and I received a replacement from PP today).

-Replaced battery twice. Have tried (2) brand-new Optima Red tops.

-Replaced ignition switch.

-Replaced all relays, including starter relay.

-Reset immobilizer.

What else can I possibly check?

If anyone has any ideas, please share them. I'm going insane right now. Thanks.

Scott

[juniinc]

voltage regulator,,,

[Divexxtreme]

voltage regulator,,,

More info: When the car was idling, I had 13.8 volts coming from the Alternator, but only 11.6 volts coming from the battery. The battery started out at 13.0 volts when I first fired the car up. The battery voltage was quickly dropping with the A/C, radio and headlights turned on.

Edited July 6, 2008 by Divexxtreme

[plima]

You have nearly identified the problem in your last update. The voltage at the alternator (which, I'm pretty certain includes the voltage regulator internally) of 13.8 volts is adequate to keep the battery from discharging, and, in fact, would actually charge the battery adequately at normal temperatures. The problem is that the terminal voltage at the battery is not high enough; anything below about 12.6 will indicate the battery is discharging, not charging. There are a couple of possibilities that I can think of. First (and I think most likely) is that you have a high resistance connection "around" the battery. I'd check the positive cable connection first; make sure the cable is robust (no broken wires), connector is clean and tightens well to the battery. Check the negative cable likewise, but, in addition, check where the negative cable attaches to the body. If it is partially broken, loose, or corroded, that is the source of the high resistance. The other possibility (I think much less likely) is that there is a high current load near the battery. I'd watch the voltage at the battery when the engine is shut off; if it doesn't drop significantly from the already low voltage you are reporting, then at least with the engine off there isn't much additional load. With the engine running it is much harder to find this kind of load; an ammeter in series with one lead of the battery will show which direction and how much current is flowing. I hope this helps.

[Divexxtreme]

The problem is that the terminal voltage at the battery is not high enough; anything below about 12.6 will indicate the battery is discharging, not charging.

Okay, this part confuses me. Are you saying that anytime the battery is below 12.6 volts, the alternator won't charge it? Meaning, for example, if I left my headlights on for a couple of hours and the battery drained down to 10 volts...driving my car would not recharge the battery after I got it jumpstarted like other cars would?

There are a couple of possibilities that I can think of. First (and I think most likely) is that you have a high resistance connection "around" the battery. I'd check the positive cable connection first; make sure the cable is robust (no broken wires), connector is clean and tightens well to the battery. Check the negative cable likewise, but, in addition, check where the negative cable attaches to the body. If it is partially broken, loose, or corroded, that is the source of the high resistance.

Cables are all good. Clean, with no broken wires or corrosion at all. They look like new.

Thanks.

[plima]

Okay, this part confuses me. Are you saying that anytime the battery is below 12.6 volts, the alternator won't charge it? Meaning, for example, if I left my headlights on for a couple of hours and the battery drained down to 10 volts...driving my car would not recharge the battery after I got it jumpstarted like other cars would?

The battery terminal voltage tells the story. If it is charged up and not connected to anything it will show something like 12.4-12.6 volts. If the voltage is below this, then the battery is discharging. If the voltage is above about 13.5 then the battery is being charged. The alternator provides the higher terminal voltage that allows charge to go into the battery. When the engine is not running or when there is a bad connection or excessive load, the battery terminal voltage will be below the level for charge to go into it, and thus the battery will discharge.

[Divexxtreme]

The battery terminal voltage tells the story. If it is charged up and not connected to anything it will show something like 12.4-12.6 volts. If the voltage is below this, then the battery is discharging. If the voltage is above about 13.5 then the battery is being charged. The alternator provides the higher terminal voltage that allows charge to go into the battery. When the engine is not running or when there is a bad connection or excessive load, the battery terminal voltage will be below the level for charge to go into it, and thus the battery will discharge.

Okay, thank you. I just returned form Autozone where I had my battery bench-tested. It passed.

So, are the below steps what I should do next?

1. Charge the battery with an external charger, let it sit....and then measure the voltage. If more than 12.4-12.6 volts...

2. Connect the battery to my car, leave the engine and all accessories/lights off (close doors and set alarm)..and then measure the voltage in an hour or so to see if there is a drain with the engine off.

3. If no drain, start the car and measure the voltage from the alternator and then from the battery terminals again. If the battery continues to drain....

.....what is my next step?

Thank you very much for the help.

Edited July 6, 2008 by Divexxtreme

[ADias]

... Connect the battery to my car, leave the engine and all accessories/lights off (close doors and set alarm)..and then measure the voltage in an hour or so to see if there is a drain with the engine off. ...

If you have a private garage I recommend you do not lock the car w/ the alarm on, as that will put a load on the battery.

The advice you got above is good - check your battery connections and cables and make sure that they are intact and make good contact. The symptoms you describe point to a resistive load hanging on the battery but not on the alternator.

Edited July 6, 2008 by ADias

[plima]

I just had another thought. If, when you start the car, the starter turns over quickly (i.e. it sounds normal, not slow like a dying battery) then perhaps the voltage drop is occurring between the alternator and the starter (possibly the cable connection at either end). The charging current flows from the alternator (where the voltage seems to be OK) to the starter. From there it goes to the battery through a very heavy cable (since that cable carries the high current from the battery required to run the starter). The basic troubleshooting path is to find the "missing" volt. Starting with 13.5 at the alternator, you should see about that at the battery when all is fine. The problem is the drop in voltage, most likely from a poor connection (high resistance) somewhere in this path.

[Tool Pants]

I have had 3 Autozone batteries, the standard lead acid type. The first 2 would not hold a charge. I would drive all day and park the car. In the morning the battery was dead. Sometimes when I got home and put the battery on a 10 amp charger, and the battery would be dead in the morning.

Each battery had a bad cell per the hydrometer test I did. A guy there would test the battery in the car in the parking lot. I would ask him what kind of test, but he never answered. He either did not know or just knows how to push a button on the battery tester. I do not know if he did a true load test. I do not think they want to find a bad battery when it is one of theirs under warranty. The last time the guy tested the battery and said nothing to me, but spoke to the manager. The manager said I would have to leave the battery so it could fully charged and then load tested.

Problem is I had the battery on a 10 amp charger for hours and drove 5 minutes down the street to Autozone. I'm not sure if they ever did a real load test. I told him he could charge the battery all day long, but the proplem was a short in one of the cells. I had the proper voltage, just not the amps. That is when I got the 3rd battery and so far no problems.

I do not know if I would rely on Autozone. More so if you got the Optimas there. If you have a local battery shop take it there.

You said this started 2 months ago. What was going on before then and what battery did you have? Did the problem start when you put in the first Optima or the first alternator? You need to give more history.

You can test the draw of the electrical system yourself. Search on milliamps. Here is one.

http://www.renntech.org/forums/index.php?s...mp;hl=milliamps

[Divexxtreme]

I have had 3 Autozone batteries, the standard lead acid type. The first 2 would not hold a charge. I would drive all day and park the car. In the morning the battery was dead. Sometimes when I got home and put the battery on a 10 amp charger, and the battery would be dead in the morning.

Each battery had a bad cell per the hydrometer test I did. A guy there would test the battery in the car in the parking lot. I would ask him what kind of test, but he never answered. He either did not know or just knows how to push a button on the battery tester. I do not know if he did a true load test. I do not think they want to find a bad battery when it is one of theirs under warranty. The last time the guy tested the battery and said nothing to me, but spoke to the manager. The manager said I would have to leave the battery so it could fully charged and then load tested.

Problem is I had the battery on a 10 amp charger for hours and drove 5 minutes down the street to Autozone. I'm not sure if they ever did a real load test. I told him he could charge the battery all day long, but the proplem was a short in one of the cells. I had the proper voltage, just not the amps. That is when I got the 3rd battery and so far no problems.

I do not know if I would rely on Autozone. More so if you got the Optimas there. If you have a local battery shop take it there.

You said this started 2 months ago. What was going on before then and what battery did you have? Did the problem start when you put in the first Optima or the first alternator? You need to give more history.

You can test the draw of the electrical system yourself. Search on milliamps. Here is one.

http://www.renntech.org/forums/index.php?s...mp;hl=milliamps

History is my crank pulley backed out during a drive. After I replaced it, I started having charging issues. I assumed that the serpentine belt quickly coming off the pulley is what caused my stock alternator to go bad. I replaced the crank pulley bolt and the serpentine belt and everything is fine with that. I then began having charging issues so after some troubleshooting, replaced the alternator with a refurb from PP and got a new Optima battery from AZ. Charging issues still remained so I replaced relays, batteries (got a 2nd Optima battery), ignition switch and reset the immobilizer. I've checked all of the heavy power/negative cables that I can and haven't found any that are dirty, damaged or have bad connections.

I then removed the "new" alternator and Autozone bench-tested it...it failed. I sent it back to PP, they sent me another one..and this one is currently putting out a consistent 13.6-13.7 volts. When the alternator sends voltage to the battery, the battery shows around 12.6-12.7 volts. But it doesn't always seem to send power to it.

IRT the batteries, I have a Odyssey battery that I had Autozone check yesterday, It passed. So I have brand-new Optima red top that I got from Autozone and a brand new Odyssey that I got from gotbatteries.com. They are both good. They have plenty of juice to start the car multiple times after they have been charged. It's when I drive the vehicle that they begine to lose power.

I just went for a long drive and tried turning off different accessories to see if I can identify one that is drawing a large current load. I'm unable to narrow it down that way. I did some checking before I took the drive, and when the car is not running, I have equal voltage between the battery, alternator and starter. One thing I did notice during the drive...is that when I'm idling at stop lights or sometimes when I'm just cruising in 6th gear at a steady speed, the alternator stops sending power to the battery. I can watch my voltmeter in my dash drop from 12.4 to 11.7 or so. Then, if I step on the gas, it will jump back up to 12.4 Only under a load does it start charging again. So if I do have a current drain, the alternator doesn't supply enough voltage to the battery to keep up. It cycles on and off and just isn't "on" enough to keep up.

So I'm starting to think that Autozone was wrong wheh they stated that I didn't have a current draw. I think I do and it seems to draw only when the engine is running. I'm going out to check for a current draw now. I'll let you know what I find out....

Edited July 6, 2008 by Divexxtreme

[Tool Pants]

Electrical problems are a pain and about all I know is how to change a light bulb. One of the best persons for electrical issues is Sandy.

I have been told you can drive a car several days with a fully charged battery even if the alternator is not charging, as long as you do not use the headlights because they draw a lot.

It appears that your battery is discharging faster than the alternator can keep it charged. I trust you are not operating a microwave or a heavy duy sound system off your electrical system. If you had one of those little racing batteries - but you have an Optima.

I do not know how to check the draw with the engine running. I guess you need the kind of amp meter that can clamp onto the battery negative cable.

What does reset the immobilizer mean?

[Divexxtreme]

Electrical problems are a pain and about all I know is how to change a light bulb.

I have been told you can drive a car several days with a fully charged battery even if the alternator is not charging, as long as you do not use the headlights because they draw a lot.

It appears that your battery is discharging faster than the alternator can keep it charged. I trust you are not operating a microwave or a heavy duy sound system off your electrical system. If you had one of those little racing batteries - but you have an Optima.

I do not know how to check the draw with the engine running. I guess you need the kind of amp meter that can clamp onto the battery negative cable.

What does reset the immobilizer mean?

I have the stock sound system. The only other electronics I have in the car are an Electronic Boost Controller and V-1 radar detector. Both of which had for a couple of years and have never had any problems with.

I checked the current draw with the car off, and it was 60mA no matter what fuse I removed. I then removed the nut where the alternator, battery and starter wires meet in the engine compartment, removed the alternator wire from the bolt...and the draw was 50mA. It was a negligible change so I don't think that's the issue.

I'm not sure how to check my current draw with the engine running other then using a current clamp...which I don't have.

I have read that sometimes the immobilizer will draw current from the car and resetting it will fix the problem. I simply unplugged the wire, then reset the error code using a Durametric cable.

Edited July 6, 2008 by Divexxtreme

[Loren]

Measure the current at the battery - 40- 60 ma is pretty normal.

[Divexxtreme]

Measure the current at the battery - 40- 60 ma is pretty normal.

It's reading 60 mA. I think my draw is occurring with the engine running. Either that, or the remanufactured Bosch alternators really suck.

Edited July 6, 2008 by Divexxtreme

[Divexxtreme]

I'm going to re-charge my battery externally and try it again. This is so unbelievably frustrating. If my alternator is putting out 13.6-13.9 volts..why the heck is my battery not charging to that level even with all accessories off?? Maybe both of my new batteries really are bad and Autozone's testing equipment is wrong.

Arrghhh.....

Edited July 6, 2008 by Divexxtreme

[Divexxtreme]

Update:

While driving, when I turn to the right and create centrifugal force towards the Driver's side of the car..the voltmeter jumps from 12.4 to to 13.8 volts. It will remain at 13.8 volts as long as I'm turning right with enough speed to create noticeable centrifugal force (i.e., while on a on or off ramp). It doesn't do it when I turn left, only right.

I assume something is pinched or loose. Any ideas?

[JeTexas]

I don't know if this is true for Porsche alternators, but most new alternators for my other cars will put out up to 14.5 volts with 13.8 being the bare minimum that's acceptable for good charging.

Is your belt tight enough? If it's slipping, that could explain why you get higher voltage turning when there might be a stretch on the chassis/engine compartment.

Also, I've had a starter solenoid cause a drain before. Might be something else to check.

[wwest]

In the battery compartment follow the negative battery lead to where it is attached to the car chasis. Make sure the connection there is good, tighten the nut holding the negative connection to the chasis while making sure the stud/bolt itself does not turn and is therefore welded FIRMLY to the chasis.

[RCasto]

If your crank pulley backed out, did it bread the indexing pin on the crank? If so the pulley may be slipping and not turnig the serpentine belt consistently.

[Divexxtreme]

Problem solved.

It seems that the nut that holds the engine to chassis ground wire in place (located on the passenger side of the car near the valve cover) had come off...causing the ground wire to move on and off the chassis ground bolt. I replaced the nut, and now all is well. I just drove the car for 2 hours and voltage is consitently maintaining just under 14 volts while driving (like it should) and the car starts and runs great again.

Thanks for all the help, guys. That was a huge PITA.

Edited July 13, 2008 by Divexxtreme

[wross996TT]

Glad it's fixed Scott...electrical is just the sh!ts.

[Chicago911TT]

Glad it's fixed Scott...electrical is just the sh!ts.

hey Scott how about a pic. I am having the same problem but only change the alternator and battery so far and still

no luck.

[PorscheFan]

I have had battery-draining problem for several weeks and couldn't solve it. I checked all the threads to see if there is solution. So far, I have checked the connection of wire, tried to pull fuse when engine is running, turn off accessories one by one,.... No luck. :(

I have not tried to reset immoblizer. Can anybody tell me how?

Another symptom of my car is the voltage drop below 12 when temp reaches 180 or above. I tried to pull the fan fuse, no luck either. Any clue?

Thanks in advance for your input.

[Loren]

With any battery drain you need to isolate the circuit the problem is on.

Usually you do this by measuring the current load with the engine off (you will need an amp meter for this). Normal is around 40-60 ma.

If it is higher then pull fuses one at a time until the current drop significantly. That circuit is the the circuit with the drain - and you will then need to see what is on the circuit that causes the problem.