Hi

I couldn't find a recent post on this problem so I will make a new
post :

** My '98 Passat (1.8 20v estate) battery goes flat if left parked for
2-3 days. **

If I drive it every day - no problems.  As soon as it is not driven
the battery goes so flat it can barely light the dashboard lights.

I've changed the battery - and the alternator - problem still exists.

I have for some years had a problem with the Comfort Computer wiring -
standard problem as described elsewhere in this forum - to eliminate
it from causing this new problem I lifted the carpets and moved the
comfort computer and fixed all the rusted out joints - so I now have
all the interior lights and central locking working again.

Any thoughts please - thanks in advance for any help.

Regards

Dicky

Hi

Do you have aVW 6 disk CD Player in your car? I had one added to my 98 Golf, 
and discovered that if I had been playing a CD when I turned the engine off 
the player went on playing to itself. (I would return to the car and find 
that it was now playing a different CD to the one I had been listening to.) 
This also caused a drain on the battery and so if the car was left unused 
for some time the battery would struggle to turn the starter.

Alternatively, you could have some other current drain discharging the 
battery (such as a boot light permanently on) but for it to act that quickly 
it sounds like a pretty significant load!

Chris

"OpenX_UK"  wrote in message 
news:8467c560-0ba5-442e-9626-52191cf27ec0@a3g2000prm.googlegroups.com...
> Hi
>
> I couldn't find a recent post on this problem so I will make a new
> post :
>
> ** My '98 Passat (1.8 20v estate) battery goes flat if left parked for
> 2-3 days. **
>
> If I drive it every day - no problems.  As soon as it is not driven
> the battery goes so flat it can barely light the dashboard lights.
>
> I've changed the battery - and the alternator - problem still exists.
>
> I have for some years had a problem with the Comfort Computer wiring -
> standard problem as described elsewhere in this forum - to eliminate
> it from causing this new problem I lifted the carpets and moved the
> comfort computer and fixed all the rusted out joints - so I now have
> all the interior lights and central locking working again.
>
> Any thoughts please - thanks in advance for any help.
>
> Regards
>
> Dicky

OpenX_UK wrote:
> Hi
> 
> I couldn't find a recent post on this problem so I will make a new
> post :
> 
> ** My '98 Passat (1.8 20v estate) battery goes flat if left parked for
> 2-3 days. **
> 
> If I drive it every day - no problems.  As soon as it is not driven
> the battery goes so flat it can barely light the dashboard lights.
> 
> I've changed the battery - and the alternator - problem still exists.
> 
> I have for some years had a problem with the Comfort Computer wiring -
> standard problem as described elsewhere in this forum - to eliminate
> it from causing this new problem I lifted the carpets and moved the
> comfort computer and fixed all the rusted out joints - so I now have
> all the interior lights and central locking working again.
> 
> Any thoughts please - thanks in advance for any help.
> 
> Regards
> 
> Dicky
How long ago did you fix the CCM? It could have been leaving a light on 
or similar.

On Sep 4, 6:32 pm, Chris Bartram 
wrote:
> OpenX_UK wrote:
[snip]
>
> How long ago did you fix the CCM? It could have been leaving a light on
> or similar.

I fixed the CCM after this problem started - in case it was the CCM
causing the problem - difficult to take the car to a car electrician
and say I know of several electrical faults - so I fixed the corroded
wiring and the CCM had already been moved up under the floor mats at
the front of the footwell, out of harms way.

From the other reply above - I do have a CD changer but it's been
there a long time and seems to be working fine.

"OpenX_UK"  wrote in message 
news:8467c560-0ba5-442e-9626-52191cf27ec0@a3g2000prm.googlegroups.com...

<snip>
> ** My '98 Passat (1.8 20v estate) battery goes flat if left parked for
> 2-3 days. **
>
<snip>

Well the good news is that given an average car battery is somewhere in the 
30 to 50 Amp/Hr capacity, you are looking for an easily measurable drain.

If we pick the high capacity end (50 amp/Hr and assume 50 hours parked, you 
are looking for about a 1A drain - ie a 12w bulb, or indeed a CD changer not 
shutting off. If it does it reliably, ie not just occasionally, any decent 
auto electrician should be able to isolate the issue.

Good luck

Dave

OpenX_UK wrote:
> On Sep 4, 6:32 pm, Chris Bartram 
> wrote:
>> OpenX_UK wrote:
> [snip]
>> How long ago did you fix the CCM? It could have been leaving a light on
>> or similar.
> 
> I fixed the CCM after this problem started - in case it was the CCM
> causing the problem - difficult to take the car to a car electrician
> and say I know of several electrical faults - so I fixed the corroded
> wiring and the CCM had already been moved up under the floor mats at
> the front of the footwell, out of harms way.
> 
> From the other reply above - I do have a CD changer but it's been
> there a long time and seems to be working fine.
> 
How about putting an ammeter inline with the battery lead and pulling 
the fuses one by one?