New member needs your help.

[Roy brown]

Hi I’m a new member and need your help. I have a boxster 981S and have a issue with the battery draining over night. So far I have checked the alternator thats fine. unplugged it over night still went flat. The ac resistor has been changed. The battery is brand new well three new batteries that’s how bad the drain is. Fully charged to flat in 2 days. I’ve done a few checks with a multimeter but in no auto electrician. There is a high amp drain but can’t find it. Can anybody help.

 

[IndischRot]

Does the car live outside? If so I would check for water under the seats from a blocked roof drain resulting in water-damaged ECUs and all sorts of strange goings on.

 

[Motorhead]

Roy,

It certainly sounds as though you have a serious current drain. If you're absolutely certain that the alternator is charging correctly, although it's a bit hit-and-miss I think your only course of action is to start pulling fuses to try to locate the source of the drain.

As Felix has mentioned, check for any damp areas around the car which could be leading to electrical shorts.

Jeff

 

[CLIFFWILKINS]

Agree with above posts but electrical drains can be hard to diagnose we found this out on a Z3 it turned out to be the radio memory draining took ages to diagnose getting through a couple of batteries.
Think it might be time for it to go into the garage to diagnose the problem. Electrical issues can be notoriously hard to diagnose.
Good luck.

 

[AlistairF]

I'd worry about looking at it myself. What with the ECU and can bus etc...

 

[hotfrog1]

I cannot guess whether your problem is a permanent drain or not but I would recommend one of these. It worked for me and is useful at anytime in the toolbox. It is a clamp meter that measure dc current among many other things: https://smile.amazon.co.uk/gp/product/B00O1Q2HOQ/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1

 

[mikeg]

Hi Roy,

A year or so ago a friend had a similar issue and found that the car had a tracker (which he didn't even know about !!!) and it had developed a fault - just a suggestion ...

 

[Roy brown]

the tracker was the first thing I got checked out. It’s brand new and is working fine. Tried a few of everyones suggestions but still going flat. It’s back to the Porsche garage I got it from on Wednesday so hopefully it gets sorted.
I will post update ASAP. Thanks for your help.

 

[IndischRot]

any news?

 

[Roy brown]

After all the test that have been done. It looks like the alternator is faulty. New one arrives today so fingers crossed. I will let you know in two days if I still have a charged battery. ??

 

[hotfrog1]

After all the test that have been done. It looks like the alternator is faulty. New one arrives today so fingers crossed. I will let you know in two days if I still have a charged battery. ??

Hope it goes well.

 

[Motorhead]

Yes, it occurred to me that maybe it's just a defective alternator diode. Hopefully a cheap and easy fix?

Jeff

 

[hotfrog1]

Yes, it occurred to me that maybe it's just a defective alternator diode. Hopefully a cheap and easy fix?

Jeff

Thanks. Hope it is that simple. The clamp meter that I mentioned above is brilliant for find where current is flowing. I fitted a new alternator on my 1981 911SC last year but could not get the alternator to fire up. The supplier suggested that it was field current issue and the clamp meter let me measure the field current directly and I was then able to fix the problem and it worked perfectly. It was associated with changing from an external voltage regulator to an internal one.

 

[Roy brown]

Hi guys and gals. Just a quick update on the battery drain. After a few hours shouting at the car the alternator is replaced by myself. All working as it should but the drain was still there. I’ve now borrowed a amp meter and found it to be the pcm ??. The issue I have now is what to do. as it works perfectly but drains the battery. Any ideas except pulling the fuse every night.

 

[andywill]

Hi Roy
Give these guys a call.
https://www.pcmrepairs.co.uk/
good luck

 

[Roy brown]

Hi everyone. Hope your all staying safe.
the battery drain issue is now fixed. It was the Bluetooth staying on when the car was switched off. Easy fix for now settings then Bluetooth then turn off. 10 seconds to stop the battery going flat ??????. Thanks again for your help trying to sort this issue.
stay safe everyone.

 

[CLIFFWILKINS]

Good news []

 

[Motorhead]

Roy,

The simple fixes are always the best - and cheapest.! Good result.

Pity you forked out on the alternator before you found the problem, but at least that's another component you don't need to worry about - unless you're able to return it for a refund?

Jeff

 

[Roy brown]

Roy,

The simple fixes are always the best - and cheapest.! Good result.

Pity you forked out on the alternator before you found the problem, but at least that's another component you don't need to worry about - unless you're able to return it for a refund?

Jeff

I wouldn’t want to remove it again as it was a pain to fit. But it’s all good. The only thing is I still cant drive it. But when we get back to normal I will enjoy it again. ??????