Starting Problem (Is It A Dead Battery Already)

[Sefo]

Please I need help I forgot to warm my mums car for about four days and when I went to warm it, I turned the ignition key on the lights in the dashboards showed but when tried to start the engine it gave a sound, the light in the dashboard became faint I switched it off after a few days went bye the car refused to open with the automatic key I told the driver and he came charged the Battery for 2hours and the car worked again but again I waited till the 2nd day to warm the car on getting there it still made that sound and the lights began to fade. MY QUESTION IS Please is the Battery dead or it hasn't been charged enough. I just want some help here before my mum goes buys a new Battery.

Its model is TOYOTA AVENSIS 2.0 V-MATIC T4 VALVEMATIC CVT AUTOMATIC 4 DOOR IN BLACK MET.

[My first toyota]

Start the car either by starting it or jump/bump start. Take it to a good mechanic who can do a Battery and alternator test.

Leave the engine running and get the alternator tested.

Turn engine off and get Battery tested.

That'll tell you if your Battery is weak or alternator. If both are fine leave it started for while to charge the battery. A poorly charged battery will come up on the battery tester anyway.

Im no expert but thats what Id do.

[fastbob72]

It does,at first reading sound like a ropey Battery but before condemning it out of hand a few questions.

You say you've been going out to 'warm' it up so does that mean the car isn't being used very often so how often is it being driven these days ??

If it's not being regularly used,only being turned over and warmed up periodically then it's not that surprising if the Battery discharges.

And putting it on charge for two hours could give it enough power to start the engine but if it's just left to idle until warm then the alternator prob isn't turning fast enough/producing enough power to both keep the electrics going and fully recharge the Battery.

Best thing to do is take it for a good long drive.Not around the town or city but out on the open road,dual carriageway or motorway.Get it up to speed and keep it there for a good while.Keep all electrics off as much as possible.i.e heater,wipers,lights,stereo etc.Try to take it for at least half an hour to get it really charged.

If it still has problems starting then there is a fault with either the battery or altenator.Check the drivebelt to see if it's lost any tension aswell.

[Valvematic]

once you allow a Battery to discharge you damage the cells within the Battery so they no longer hold charge as designed.

[fastbob72]

Mm,aye Valvem that's true up to a point but it takes being discharged/recharged many,many times to impair the battery's performance appreciably or else I'd have been buying new battery's monthly when I was younger and running around in Escorts/Cortinas and Capris.lol.

I've had battery's I've kept from car to car.I've had one that I got with a Rover V8 engined Capri.It was in good condition and because it was a big Battery with a beefy Ah rating (considering it was expected to cope with starting a 3.9 V8) it was worth keeping.Whenever I got another car I'd remove it's Battery and use that one,then swap it back when I sold or scrapped it but it'd also sit in my open garage at other times often losing it's charge after a fair while but bang it back on the charger overnight,good as gold.

It's sitting in my Avensis's engine bay right now and I've had it near 10 years !!!

A good quality Battery can take serious long term use and abuse before it takes any noticeable damage,performance-wise.Discharging will cause a breakdown of the acid causing lead sulphate to form on both the +ve and -ve plates plus oxygen escsapes from the +ve plate and mixes with the electrolyte to produce water which dilutes the acid but obviously it takes a significant change in the plates and acid to effect overall performance.The battery's performance is dependant on several things like the strength of the acid,the surface area of the plates,it takes a lot of minute deposits on the plates to reduce that surface area of a large volume of water (in the sense of the percentage of the battery's acid capacity) to significantly dilute the acid.

Also a battery,even a brand new one will slowly discharge over time with lack of use which is going to do more damage than continual use/discharge/recharge.

FB.

[waqar_lionheart]

Agreed with All of you. However, just wondering if this car has a bad earth, would it discharge the Battery???

[fastbob72]

I suppose it's maybe possible it could be a bad earth but it wouldn't cause the Battery to discharge and go flat.

In fact,bad earth connections tend to cause more intermittent faults or a complete failure though an earth that's bad can cause the contact to overheat or spark it's less likely to flatten the Battery