968 battery Drain

[bazhart]

Hi - Its a bit embarrasing to have to ask for help but I haven't worked on the cars themselves for probably 20 years and was never much good at electrics anyway.

My neighbour has a beautiful late 968 Tiptronic (which I helped him acquire) and I am trying to help with. His battery drains over about 24 hours and there is a permanent 3 amp drain that we cannot find the cause for.

I have checked all lights (under bonnet and glove box etc) and the radio. Cannot even find where the siren is to see if the alarm system is taking the drain - but the alarm fuse does not isolate it.

It must be well over 20 years ago that I last worked on a 968 (and then probably pre-airbag models) and we always used to get in an alarm expert back then when there were issues - so I am not the best person to help anyway.

I do seem to remember the standard alarms having quite a high drain and many owners replacing them with something more modern.

Any ideas, suggestions or recommendations or do you know of anyone that might be more familiar with it in the North West Bolton area?

Thanks guys,

Baz

 

[Wh1t3Kn1ght]

Hi Baz,

Not sure if it is the same on the 968, but on my '90 944 Turbo the factory (think they were fitted by the dealer actually) hamilton palmer alarm system is underneath the passenger seat. The company still provide support according to some forum posts I've seen in the past.

Dave

 

[taffybloke]

Hi Baz, I had a similar issue with my 996 and it turned out to be an old Tracker that had a failed battery and was causing a draw.

Mike

 

[deMort]

A 3 amp drain is pretty high .. alarm / radio would be my first thoughts but 3 amp is above the norm for these ..

It's also well above an aftermarket tracker system ... this tends to be a pulsed discharge of an amp and not 3 amps .

I would use an amp hound on each fuse with the car locked to find which fuse the drain was on .. if no fuses show a discharge then things like alternator are a possible issue ..

Link to an amp hound here but its the first one after a search so you might find cheaper ..

https://gb.jbtools.com/cal-van-tool...MI3tu1k7q48QIVFevtCh0IxQtYEAQYASABEgLlcvD_BwE

This basically connects to each side of a fuse and gives a read out of the current draw on that particular fuse .

Its a process of elimination basically and as in the case of an alternator .. it may not be a draw on a fuse .

The alarm siren is basically a horn ( no battery in it ) .. an issue here on the later cars and it blows the alarm fuse .. trip the alarm to locate it .. i think its bulkhead area but i'm not sure .

An aftermarket alarm fitted is a good point to start along with any other after market items .. over the years its not uncommon to see several alarm systems fitted ... these do have sirens along with internal batterys .. but again 3 amps is pretty high for an issue here.

If it was a bit higher i would almost be thinking an electric seat motor has got stuck !!

I have 92-95 wiring diagrams if you need them .

It's a dam shame the customer is not further South .. its the kind of job i enjoy .. these days a challenge is all that keeps me working lol .

 

[kas750]

Seat motor is a good call

 

[Wh1t3Kn1ght]

Just had a thought about the window motor / courtesy light circuit. Maybe the earth points for the door switches are not working right? When the switch is activated (door opened) it engages a relay to allow the windows to be operated with the ignition off, could it be that this relay or another is permanently live and causing the drain?

Have you tried pulling relays out to see if the drain can be pin-pointed to a specific relay circuit?