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sboost

Something seems to be Draining my Battery

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On 2 subsequent occasions now I've gone to start my 2000 Boxster about 24 hours after last driving it, and found the battery to be completely drained. I thought the problem might be the battery itself but after fully charging it and leaving it disconnected for 2 days it held the charge and started the car OK as soon as it was reconnected. The battery is only 2 years old and when I store the car I've always used the Porsche trickle charger.

With the car and all the lights and accessories off, I measured a current drain of about 2.5 Amps at the battery post. Does anyone know if this is normal? It seems high to me but I'm curious to know if it could be just an initial current for some system that remains active for a short period before going to "sleep". I tried pulling fuses one at a time for any and every system with an electronic controller (central alarm etc.), but the reading stays at 2.5 Amps. Funny thing is, absolutely everything on the car works fine (central lock, remote, windows, radio, lights, everything!)

Does anyone know if the 2.5 Amp reading is normal, or experienced a similar problem?

Without some advice my options are now:

1) Replacing the battery (which could be for no reason if it's a problem with the car's electrics), or even worse I could end up damaging the new battery from deep cycling it one two many times!

2) Bring the car to the stealership (please God No).

Anybody have any ideas?

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I suggest:

1. Have your battery tested at a car parts store.

2. If it is okay, then measure the load (amps) when the car is off - should be around 40-60 ma).

If it is more pull fuses one at a time until the drain goes away. When the fuse you pull brings the load back down to 40-60 ma then you have found the cicuit with the problem. Once you've done that report back here what fuse and we'll tell you what is on the circuit and suggest what to look for.

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http://www.pca.org/tech/tech_qa_question.a...9-284D52B42EDE}

http://www.pca.org/tech/tech_qa_question.a...7-84710F816889}

If you measured correctly then 2.5 amps is way too high.

A few years ago my battery would be dead in the morning after I had driven the car a long time the day. This happened several times. I would even put the battery on a 10 amp charger for several hours and next morning it was dead. But the battery (from Autozone) had been replaced about a year later.

I hooked up my meter to see if somehing was draining the replacement battery. Not an electrical guy. When I look at the picture I had the meter dial set to 10 amps. I should have used a smaller scale. At the 10 amp setting it was .04 which I assume was 40 milliamps. Peter Smith says no more than 40 milliamps. Scott Slauson says about 20 miliamps. So I ruled out the car as being the cause of a dead battery.

Autozone tested the replacement battery and gave me another.

If you are positive the draw is 2.5 amps then the problem is with the car. Even if the trunk lights were on when you tested the 2 little trunk light bulbs are not going to draw 2.5 amps.

While your meter is on you are suppose to pull one fuse after the other to determine which circuit is causing such a high draw.

post-4-1182357942_thumb.jpg

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On 2 subsequent occasions now I've gone to start my 2000 Boxster about 24 hours after last driving it, and found the battery to be completely drained. I thought the problem might be the battery itself but after fully charging it and leaving it disconnected for 2 days it held the charge and started the car OK as soon as it was reconnected. The battery is only 2 years old and when I store the car I've always used the Porsche trickle charger.

With the car and all the lights and accessories off, I measured a current drain of about 2.5 Amps at the battery post. Does anyone know if this is normal? It seems high to me but I'm curious to know if it could be just an initial current for some system that remains active for a short period before going to "sleep". I tried pulling fuses one at a time for any and every system with an electronic controller (central alarm etc.), but the reading stays at 2.5 Amps. Funny thing is, absolutely everything on the car works fine (central lock, remote, windows, radio, lights, everything!)

Does anyone know if the 2.5 Amp reading is normal, or experienced a similar problem?

Without some advice my options are now:

1) Replacing the battery (which could be for no reason if it's a problem with the car's electrics), or even worse I could end up damaging the new battery from deep cycling it one two many times!

2) Bring the car to the stealership (please God No).

Anybody have any ideas?

Well the way everyone used to check the draw at the dealer was with a clamp on low ammeter. You clamp around the negative cable. Using a

Dvom is no good cause they usually turn off automatically and switching it on wakens the ecu's. First off you must let the car sit for at least 2-3 hours, make sure to manually lock the hood latch and leave the door open and also manually lock the latch. The draw per factory specs is max 36ma

Now I agree with you, dont go to the steelership, thank god I dont work there any more, most of the guys there Hacks, parts changers who just wanted to fix your car so it came back. but if you must take it, request that the shop forman do the repair.

vizcarra

vizcarra44@yahoo.com

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On 2 subsequent occasions now I've gone to start my 2000 Boxster about 24 hours after last driving it, and found the battery to be completely drained. I thought the problem might be the battery itself but after fully charging it and leaving it disconnected for 2 days it held the charge and started the car OK as soon as it was reconnected. The battery is only 2 years old and when I store the car I've always used the Porsche trickle charger.

With the car and all the lights and accessories off, I measured a current drain of about 2.5 Amps at the battery post. Does anyone know if this is normal? It seems high to me but I'm curious to know if it could be just an initial current for some system that remains active for a short period before going to "sleep". I tried pulling fuses one at a time for any and every system with an electronic controller (central alarm etc.), but the reading stays at 2.5 Amps. Funny thing is, absolutely everything on the car works fine (central lock, remote, windows, radio, lights, everything!)

Does anyone know if the 2.5 Amp reading is normal, or experienced a similar problem?

Without some advice my options are now:

1) Replacing the battery (which could be for no reason if it's a problem with the car's electrics), or even worse I could end up damaging the new battery from deep cycling it one two many times!

2) Bring the car to the stealership (please God No).

Anybody have any ideas?

Ohms law is watts equals amps times volts (easy to remember "what are virgins") 2.5 amps is 30 watts so more than one bulb, perhaps a radio amp ?

put a clamp meter on and draw fuses - this will nail the blighter

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My saga continues.

Yesterday I did some additional checks.

First let me confirm that the current drain I'm reading is 2.5 Amps. I'm measuring it with a multimeter across the negative battery post. I removed each and every fuse (not one at a time but all together just to be sure) from the main fuse block and the reading dropped to about 2.3 Amps.

So what next?

From what I can gather from searching this forum the next logical step would be to try disconnecting the alternator. Does anyone know if the alternator is fused or exactly where the simplest location would be to disconnect it?

The only other idea I had was that it might be a Boomerang alarm system draining the battery. I know that the previous owner of the car originally had a Boomerang installed that he later cancelled. I'm assuming that he probably just cancelled the service with Boomerang but never disconnected or removed the unit from the car. Does anyone know where these alarms are typically installed on the car or where they typically draw power from? Myself I have no idea where to look for it or what it even looks like.

I should also add that I replaced the ignition switch a couple of months ago. I had the typical symptom where the radio would sometimes stay on after the key was removed. All is fine since I replaced the switch, and in either event I don't think it could be my problem because I assume all of the switch connections are fused.

Let me say that this car is my first Porsche and the help that this forum has provided me on several occasions has been invaluable. I love the car and this forum has helped make the whole Porsche experience so far very enjoyable. Without this forum, I would have probably ended up bringing my car to the dealer for every little problem that I've had. I can say with absolute certainty that if that would have been the case this would have been my first and last Porsche.

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My saga continues.

Yesterday I did some additional checks.

First let me confirm that the current drain I'm reading is 2.5 Amps. I'm measuring it with a multimeter across the negative battery post. I removed each and every fuse (not one at a time but all together just to be sure) from the main fuse block and the reading dropped to about 2.3 Amps.

So what next?

From what I can gather from searching this forum the next logical step would be to try disconnecting the alternator. Does anyone know if the alternator is fused or exactly where the simplest location would be to disconnect it?

The only other idea I had was that it might be a Boomerang alarm system draining the battery. I know that the previous owner of the car originally had a Boomerang installed that he later cancelled. I'm assuming that he probably just cancelled the service with Boomerang but never disconnected or removed the unit from the car. Does anyone know where these alarms are typically installed on the car or where they typically draw power from? Myself I have no idea where to look for it or what it even looks like.

I should also add that I replaced the ignition switch a couple of months ago. I had the typical symptom where the radio would sometimes stay on after the key was removed. All is fine since I replaced the switch, and in either event I don't think it could be my problem because I assume all of the switch connections are fused.

Let me say that this car is my first Porsche and the help that this forum has provided me on several occasions has been invaluable. I love the car and this forum has helped make the whole Porsche experience so far very enjoyable. Without this forum, I would have probably ended up bringing my car to the dealer for every little problem that I've had. I can say with absolute certainty that if that would have been the case this would have been my first and last Porsche.

The alternator needs to be disconnected at the alternator itself, What can happen is the diode pack within the alternator fails (Diodes only allow current in one direction) the alternator in this failed state then draws current like an electric motor.

It is a lot more technical than this explanation but this is the gist as i dont know how familiar you are with auto electrics.

You will also have to trace any additional equipment added to the car

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My saga continues.

Yesterday I did some additional checks.

First let me confirm that the current drain I'm reading is 2.5 Amps. I'm measuring it with a multimeter across the negative battery post. I removed each and every fuse (not one at a time but all together just to be sure) from the main fuse block and the reading dropped to about 2.3 Amps.

So what next?

From what I can gather from searching this forum the next logical step would be to try disconnecting the alternator. Does anyone know if the alternator is fused or exactly where the simplest location would be to disconnect it?

The only other idea I had was that it might be a Boomerang alarm system draining the battery. I know that the previous owner of the car originally had a Boomerang installed that he later cancelled. I'm assuming that he probably just cancelled the service with Boomerang but never disconnected or removed the unit from the car. Does anyone know where these alarms are typically installed on the car or where they typically draw power from? Myself I have no idea where to look for it or what it even looks like.

I should also add that I replaced the ignition switch a couple of months ago. I had the typical symptom where the radio would sometimes stay on after the key was removed. All is fine since I replaced the switch, and in either event I don't think it could be my problem because I assume all of the switch connections are fused.

Let me say that this car is my first Porsche and the help that this forum has provided me on several occasions has been invaluable. I love the car and this forum has helped make the whole Porsche experience so far very enjoyable. Without this forum, I would have probably ended up bringing my car to the dealer for every little problem that I've had. I can say with absolute certainty that if that would have been the case this would have been my first and last Porsche.

The alternator needs to be disconnected at the alternator itself, What can happen is the diode pack within the alternator fails (Diodes only allow current in one direction) the alternator in this failed state then draws current like an electric motor.

It is a lot more technical than this explanation but this is the gist as i dont know how familiar you are with auto electrics.

You will also have to trace any additional equipment added to the car

Agian if you had the right tool you would be able to diagnose this problem quickly, the dvom is not the way to go. Now to isolate this draw without having to remove the alternator I would first remove the connector to the ignition switch, pin 50 is excite voltage to alternator. If draw is gone then it is your alt. If not then I would take off engine cover and right by the power steering resevior is the Terminal 30 permanent B+ disconnect that to isolate if draw is from alt or something in the engine compartment. Agian if draw is not from alternator, check your alarm module under seat, sometimes the connectors get corroded and cause a draw, also pull the fuse and check for corrosion.

vizcarra44

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I spoke to a mechanic I know at my local dealer today. He said the tracking devices do not draw that much. He thought it was more likely the alternator or maybe the starter.

He said to do what vizcarra44 sugggested. It has been a long time since I looked, but there is a little black box with a cover on it in the engine compartment. Under that cover are 2 cables that are bolted together with a nut. I think those cables hook up the battery to the alternator and starter. Remove the nut and disconnect those cables. Then test the draw.

post-4-1182448089_thumb.jpg

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Success !!!!

I disconnected the alternator terminal exactly where Tool Pants mentioned and the drain dropped from 2.5 Amps to about 20 mA.

So now I'm focused on replacing the alternator. I sized up the job and don't expect it to be a problem for me. From what I've read in this forum, it's very likely that the problem is not the alternator itself, but the voltage regulator. A couple of people mentioned that they replaced just the regulator. I did a check on ebay and couldn't find one. Does anyone know the Bosch P/N for the regulator or where to get one?

My car is a 2000 986, 2.7l, 5 speed manual.

I found this alternator on ebay but not sure if it matches mine.

http://cgi.ebay.ca/Porsche-911-Boxster-Bos...1QQcmdZViewItem

From the Porsche parts catalogue I can see that the manual cars had a different alternator then the Tiptronic models. The alternator for manual cars like mine are supposed to have "pulley with free wheel lock" whatever that is ?

The Porsche catalogue shows 2 different part number units for manual cars: 996 603 012 02 and 996 603 012 01

Does anyone know which one would be correct for my car and the equivalent Bosch part number ?

Thanks a lot Tool Pants, Loren, Glyn, and vizcarra44 for all the help.

I think it's about time for another forum contribution.

Steven

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Success !!!!

I disconnected the alternator terminal exactly where Tool Pants mentioned and the drain dropped from 2.5 Amps to about 20 mA.

So now I'm focused on replacing the alternator. I sized up the job and don't expect it to be a problem for me. From what I've read in this forum, it's very likely that the problem is not the alternator itself, but the voltage regulator. A couple of people mentioned that they replaced just the regulator. I did a check on ebay and couldn't find one. Does anyone know the Bosch P/N for the regulator or where to get one?

My car is a 2000 986, 2.7l, 5 speed manual.

I found this alternator on ebay but not sure if it matches mine.

http://cgi.ebay.ca/Porsche-911-Boxster-Bos...1QQcmdZViewItem

From the Porsche parts catalogue I can see that the manual cars had a different alternator then the Tiptronic models. The alternator for manual cars like mine are supposed to have "pulley with free wheel lock" whatever that is ?

The Porsche catalogue shows 2 different part number units for manual cars: 996 603 012 02 and 996 603 012 01

Does anyone know which one would be correct for my car and the equivalent Bosch part number ?

Thanks a lot Tool Pants, Loren, Glyn, and vizcarra44 for all the help.

I think it's about time for another forum contribution.

Steven

In England specialist stopped suplying parts for alternators and starters years ago, I used to be able to get any single part and pay peanuts for it, but now its replace the whole thing - at least you know the cause of the problem and can now rectify

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You should have the alternator tested to make sure it was the problem and if it can be fixed, or does it need to be replaced.

Here is info on the regulator if that is the problem. http://www.renntech.org/forums/index.php?s...amp;hl=transpro

Your ebay link does not work. If you need another alternator. http://www.6speedonline.com/forums/showthr...481#post1138481 Too bad the 6speed 996 guy did not get back on the Autozone alternator as Autozone is down the street from me. Autozone has an alternator listed for your Boxster for $224.91 USD. You have car parts places like Autozone in Canada.

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On 2 subsequent occasions now I've gone to start my 2000 Boxster about 24 hours after last driving it, and found the battery to be completely drained. I thought the problem might be the battery itself but after fully charging it and leaving it disconnected for 2 days it held the charge and started the car OK as soon as it was reconnected. The battery is only 2 years old and when I store the car I've always used the Porsche trickle charger.

With the car and all the lights and accessories off, I measured a current drain of about 2.5 Amps at the battery post. Does anyone know if this is normal? It seems high to me but I'm curious to know if it could be just an initial current for some system that remains active for a short period before going to "sleep". I tried pulling fuses one at a time for any and every system with an electronic controller (central alarm etc.), but the reading stays at 2.5 Amps. Funny thing is, absolutely everything on the car works fine (central lock, remote, windows, radio, lights, everything!)

Does anyone know if the 2.5 Amp reading is normal, or experienced a similar problem?

Without some advice my options are now:

1) Replacing the battery (which could be for no reason if it's a problem with the car's electrics), or even worse I could end up damaging the new battery from deep cycling it one two many times!

2) Bring the car to the stealership (please God No).

Anybody have any ideas?

Well the way everyone used to check the draw at the dealer was with a clamp on low ammeter. You clamp around the negative cable. Using a

Dvom is no good cause they usually turn off automatically and switching it on wakens the ecu's. First off you must let the car sit for at least 2-3 hours, make sure to manually lock the hood latch and leave the door open and also manually lock the latch. The draw per factory specs is max 36ma

Now I agree with you, dont go to the steelership, thank god I dont work there any more, most of the guys there Hacks, parts changers who just wanted to fix your car so it came back. but if you must take it, request that the shop forman do the repair.

vizcarra

vizcarra44@yahoo.com

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On 2 subsequent occasions now I've gone to start my 2000 Boxster about 24 hours after last driving it, and found the battery to be completely drained. I thought the problem might be the battery itself but after fully charging it and leaving it disconnected for 2 days it held the charge and started the car OK as soon as it was reconnected. The battery is only 2 years old and when I store the car I've always used the Porsche trickle charger.

With the car and all the lights and accessories off, I measured a current drain of about 2.5 Amps at the battery post. Does anyone know if this is normal? It seems high to me but I'm curious to know if it could be just an initial current for some system that remains active for a short period before going to "sleep". I tried pulling fuses one at a time for any and every system with an electronic controller (central alarm etc.), but the reading stays at 2.5 Amps. Funny thing is, absolutely everything on the car works fine (central lock, remote, windows, radio, lights, everything!)

Does anyone know if the 2.5 Amp reading is normal, or experienced a similar problem?

Without some advice my options are now:

1) Replacing the battery (which could be for no reason if it's a problem with the car's electrics), or even worse I could end up damaging the new battery from deep cycling it one two many times!

2) Bring the car to the stealership (please God No).

Anybody have any ideas?

Well the way everyone used to check the draw at the dealer was with a clamp on low ammeter. You clamp around the negative cable. Using a

Dvom is no good cause they usually turn off automatically and switching it on wakens the ecu's. First off you must let the car sit for at least 2-3 hours, make sure to manually lock the hood latch and leave the door open and also manually lock the latch. The draw per factory specs is max 36ma

Now I agree with you, dont go to the steelership, thank god I dont work there any more, most of the guys there Hacks, parts changers who just wanted to fix your car so it came back. but if you must take it, request that the shop forman do the repair.

vizcarra

vizcarra44@yahoo.com

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