Battery going flat every 4 days

[Andy]

Can anyone shed any light on why the battery in the Elise is discharging every 4 to 5 days? Old problem of a lot of relay clicking and the headlights turn themselves on when you try to crank the engine

The battery charge light is not coming on to warn of alternator issue, the alternator and battery are both new this year.

Cheers

Andy

[steve_weegie]

Goosed battery would be my first bet, else you're looking for a sustained current drain when the ignition is off. The elise battery isnt the largest in the world to start with, and i had to replace mine 6 months ago due to similar symptoms

[meatball]

I agree....its gubbed. You can test this with a meter?

[robin]

I would check that your brake lights aren't sticking on or even coming on all by themselves from time to time.

You also need to check for current drain when the ignition is off. You can do this easily with a multi-meter set to ammeter mode.

Turn off the ignition, loosen the -ve terminal of the battery but don't remove it yet, clear the alarm/immob with the plip (assuming it's auto-armed, which it generally will have done). Then quickly remove the lead from the -ve terminal before the alarm re-arms.

Put your ammeter in 10A mode - usually this requires the red lead to be moved into an alternate socket labelled 10A.

Now you need jump leads or similar leads with crocodile clips so that you can clip one lead end onto the -ve terminal of the battery and the other end onto the black probe of the meter. Then clip the other jump lead to the red probe at one end and then onto the -ve lead that was connected to the battery - note be sure that all the actual wires that join together at the battery terminal are in fact making good contact ... easiest way is to retighten the pinch bolt I think.

The ammeter will now read what the drain current is. It'll probably be 00.0 or 00.1 which is OK - the S2 battery is something like 50Ah I think so you can draw 100mA for 500 hours or 20 days-ish. If your battery is in good order and you're seeing it discharge in 4 days (I'm assuming you're not starting the car in this time and that you've run the engine for an hour or so to charge the battery to start with) then you're looking for a drain current of about 500mA. If you see that, or more, then you need to track it down. If you see just 100mA-ish then your battery is perhaps gubbed OR you have something like a tracker or some other gadget fitted that is waking up at night and using loads of current when nobody is looking.

You can test the battery is in reasonable order by checking the voltage on cranking from fully charged - you can disconnect the plug-top coil loom to prevent it actually starting (or remove the fuel pump fuse). It should be 12.5V or greater before you start cranking and it should hold greater than 10v after about 30s of cranking. If the voltage drops off very quickly (i.e. you only get about 10s of healthy cranking before it starts to chug) then the battery is gubbed.

Finally you need to check that when you turn the ignition on but don't start the engine the alternator warning light is lit. It should then go out when you start the engine.

Cheers,
Robin

[Jacobite]

Thanks Robin ~always wanted to know how to do that properly ~ give me a recipe any day

I've not long finished fitting an Optima battery in the silver car

http://www.optimabatteries.se/installation_guide/

Spiral wound technology, sealed under compression and retains massive amounts of charge even after 18 months with out use ~not cheap I'll give you that but found one on E-bay in Paddock 4X4 's shop for much less than on- line shop 50Ah one is the same dims end on as the std battery but has 815amps cold cranking
cheers Hamish

[robin]

I was wondering whether for racing use a lithium polymer replacement battery wouldn't be a good product ... obviously it wouldn't have the same capacity as the real thing, but enough to start the car and race and would weigh nothing in comparison to the real thing ...

Cheers,
Robin

[Andy]

Thanks for the advice Robin Battery was drawing 0.001A with the engine/immobiliser off. From fully charged it survived 15 seconds of cranking before it got to sub-6V

Battery now replaced, hopefully now sorted.

Thanks again people

[Peter76]

Battery now replaced, hopefully now sorted.

Andy, what type of battery did you buy? I'm needing a new one but haven't removed the old one yet to check exactly what i need? Any part no would be a great help!

[s29ttc]

I have just invested in a accumate from http://www.thegreenreaper.co.uk/showdetails.asp?id=761 £35 delivered to my door.

Same as http://www.eliseparts.com/shop/index.ph ... cts_id=530 but eliseparts where a bit dearer.

I just leave it plugged in in the garage and it keeps the battery healthy and chargered and you dont need to ever worry about the battery going flat.

[Andy]

The battery I needed was an 063 but the Toyota engined cars need a different size, sorry.

[hiscot]

i fitted one of these to my s1
http://www.mx5parts.co.uk/product_info. ... cts_id/635
slightly smaller and lighter they require a accumate type charger being a gel battery
the £12 one from liddel works a treat