What's likely to be wrong with this car?

I was going to ask if you had access to a DVM but on reflection it sounds like an intermittent fault.

Is this car of an age when they were fitted with an OBD connector? If so then a pod connected to either a laptop or a phone will give a continuous voltage reading.

It's not a VW is it? The reason I say is a friend had a similar problem to do with updated software and a subsequent current drain.

Could be the alternator, but I'd double check the battery connections and the earthing from the battery to the chassis. Could also be a starter motor problem, check the spade connector terminal on it.

Something is discharging the battery. Either the battery is duff and is discharging itself or there is an electrical fault which is drawing current from the battery when the car is parked.

To find out which, leave the car overnight and then measure the battery voltage. Chances are that it will have gone down a lot. Then charge it and run the car and then disconnect the battery before leaving it overnight. If it has still gone down, the battery is duff. If it hasn't, you need to investigate the 'leak'.

That wouldn't explain number 6.

Several miles isn't enough to charge a battery especially this time of year when you may have the heated front/back screen operational and/or driving with the lights on.

My guess that something electrical isn't switching off. A friend once had similar problems and found the the tailgate switch for the light in the 'boot' had failed and the light was permanently on - only found when the rear parcel shelf had been removed and the light could be seen at night.

Try buying a voltmeter that fits in the power socket / cigarette lighter It should show 14+ Volts when the alternator is charging the battery (perhaps after a good few miles of driving and with lights and screen heater off)

Ebay listing taken at random

OR

And f***ed. Buy a new battery.

You might be right, but is that the only way you're able to express yourself?

A few miles on a uncharged battery results in a still uncharged battery

Depends how many miles and whether or not on those specific occasions the battery was actually 'uncharged' to start with - and he/she did say 'several miles'.

Shagged battery would be my first guess. What would you call "fairly new"?

Until that point I was going to say knackered batteyr and cold. Batteries these days sometimes have a hydgrometer built in. Little sight thingy that probably shows green for OK and black for Not OK.

Some one else has mentioned poor battery connections. Check those and all the connections involving thick cables, battery to starter motor, battery to chassis and chassis to engine block, there should be one and probably more earth straps from engine to chassis. Try using half a jump lead set to connect engine block to battery (chassis coonected terminal) and see if it starts a better. Another check is to touch each connection after you've tried and failed to start the engine, the faulty ones will be warm if not hot...

En el artículo , Joe Bloggs escribió:

Yeah, yeah. Now f*ck off.

Take it to a garage and ask for a drop test - that will verify that one way or another, quickly.

Next, get a volt meter that plugs in the cigarette socket (ebay, amazon, cheap as chips).

Drive and if it doesn't get to at least 14V your alternator (or wiring) has a problem.

The battery on both those occasions was charged well enough to start the car.

Daniele

That's what I thought, which is why this battery is fairly new. Unfortunately, despite the change of battery, the problem slowly continued to get worse.

In fact, after I changed the battery, I realised I'd changed the battery once before and had simply forgotten that!

So I don't believe the problem is the battery itself.

Daniele

Thought FUBAR was military (army) in origin?

Donno.

Yep one must make the distinction between f***ed (spontaneously broken) and buggered (some one broke it).

After having to get a couple of the lads at Wickes to bump start me after I had loaded half a ton of ballast in it, my fix is to carry one of these all the time:

Even my wife can use it! Usually at Sainsburys though.

Also handy as it will recharge a mobile or satnav even when parked up.

Quick guess. The alternator has a diode failed short circuit. Which is not only discharging the battery when the engine is stopped, but preventing the alternator from giving the full charge too.

Of course it could be other reasons. A few minutes with a decent DVM can measure any current flow with the engine switched off - and the output of the alternator.

Are you perhaps thinking of SNAFU?