964 C2 Battery Drain

[993 C4]

Can anyone offer any comments on the typical drain rate that one should expect during long periods of storage ? She is fitted with a Clifford Concept alarm / Immob which for sure, constantly drains the battery. Other than this and I guess the clock, I can't think of anything else that would drain her. She is kept in a warm dehumidified garage under a cover along side the RS.
My issue is that I fitted a new Varta Battery 3 weeks ago and despite the car being un used for the past 16 days, it is now completely flat. I've put the battery on a slow 2 amp charge tonight and will give her a good run over this weekend.
Assuming the new battery is not faulty, do you think a plumbed in trickle charger is the route to go with these cars, baring in mind she is only used about twice a month at the moment ?
I've never had this issue with the RS and that's used even less, and it runs with a smaller battery !

Thanks in advance guys.

Nick.

 

[tim_haskins]

I keep mine attached to battery conditioner...

I have had the same issues. Things to check are the door,boot and bonnet switches as these sometimes cause issues other than that I think it's a 964 thing!!

Tim

 

[Melv]

Bonnet light frequently defaults to 'on' -check the switch....

 

[Gazza3501]

I have no problems now I use an optimate battery conditioner always connected in the garage. Mine drains in a week if not. Have not yet investigated but i know the previous owner had battery charge loss problems investigated by OPC and this is the third battery (3 in as many years before my ownership). I have removed my luggage/engine compartment bulbs so its not that. I suspect the alarm system.

 

[993 C4]

Thank's Melv, Tim & Gazza.

Removed luggage compartment bulb even though switch seems ok & turned the interior lights off ( becoming a bit captain paranoid over this ! ) Should be fully charged by the morning & will give her a run then and see.....

Thanks again.

Nick.

 

[Gordon Attar]

3/4 weeks maximum on a battery so 2 weeks on a new one means somethings wrong........ Your going to have to start with a Bosch hammer check from your local friendly specialist and go from there. Its always worth checking the car over in the dark for any lights that are still on. In the meantime make sure you eave it on the trickle charger .

 

[colin129]

Following previously reported problems with my battery discharging in 4 days & finally frying itself when I tried to recharge it, I have now fitted a new battery & disconnect the earth terminal when I'm not using it. I don't have a garage so I can't keep the conditioner connected all the time.

At least it will always be available when I want to use it, instead of always praying that the battery has enough juice in it to start her up.

 

[Melv]

disconnect the earth terminal when I'm not using it

Fit a Dis-Car-Nect

http://www.holden.co.uk/displayproduct.asp?pCode=020.012

 

[colin129]

ORIGINAL: Melv

disconnect the earth terminal when I'm not using it

Fit a Dis-Car-Nect

http://www.holden.co.uk/displayproduct.asp?pCode=020.012

What's the practical difference between that & this:

http://www.ebay.co.uk/itm/Porsche-911-968-944-993-964-Battery-Isolator-Cut-Off-Switch-fuselink-/120865151753?pt=UK_CarsParts_Vehicles_CarParts_SM&hash=item1c241fdb09#ht_1053wt_1185

Also, silly question, this fits to the earth terminal, right?

 

[Gazza3501]

ORIGINAL: Melv

disconnect the earth terminal when I'm not using it

Fit a Dis-Car-Nect

http://www.holden.co.uk/displayproduct.asp?pCode=020.012

I thougt of this also but the fitting of a Dis-Car-Nect will not solve the problem surely? because there is still a wire connection as described for ancillaries/alarm etc and this will still allow a gradual slow drain.

 

[Melv]

You take the fuse out of the wire connection to kill the system.....[8|]

 

[Gazza3501]

Doh! [:-]

 

[colin129]

I've more or less decided to get one of these Discarnect devices.

I was looking at my battery & trying to work out how to fit the thing. My earth cable is 'just' long enough to reach the earth terminal and there is very little clearance around the battery.

Perhaps someone who has one might like to pop out & take a pic of it installed & post it on here, so that I can see how I am going to fit it.

I would be most grateful!

 

[colin129]

Pretty please...[&:]

 

[Steve Brookes]

Can't help you with your question Colin but I can't help thinking that your better course of action is find the battery drain and fix it. Get an autoelectrician to sort it if you need to. As you know, mine developed a bad drain (flat within 3 or 4 days) and I traced it to a combination of the window relay and the courtesy light relay. A new window relay and removing the courtesy relay fixed it.

 

[colin129]

That's ultimately what I will be doing, but even when everything was right I would be lucky to get 2 weeks out of the battery.

There is nothing worse than waking up to a nice sunny day, looking forward to finally getting the car out & not being able to start it.

It will double up as an anti-theft device too, for added piece of mind.

 

[Melv]

Seem to remember when I fitted a Discarnnect to my old C4 I had to change the earth lead.....

Sounds as tho u have an earth prob. Was recently having discharge probs on 2YO batt on my Shogun and then found that earth terminal was a bit loose!! Fingers xed that has worked as two-three days without use saw it needing a booster start.

There a a huge no. of earthing points on the 964 -maybe worth working thru them all and cleaning em up and checking tightness -however the most inaccesible one is from the bodywork to the gearbox...best of luck...