Car Repair

hwyadcloff

I have a 52-reg Ford Ka which has a recuring problem which has been looked at twice - by a roadside AA engineer & our local garage, neither of which has been able to find the cause

If the car is not driven for more than 48 hours the battery goes completely flat. (At least it re-starts reasonably easily on jump leads)

I've been through three batteries - all brand new. All were tested and found to be OK

The local garage took it in for a morning and confirmed that they'd done a full search for anything that might be draining the battery, including for example looking for a concealed light tucked away and switched on somewhere in the boot, but they
couldn't find anything

Is there anyone out there who might have any ideas?

vaio

Auto electrician will trace the current draw but might take a while (and therefore ££)

KA forum might disclose someone who has been through the same before that will point you in the right direction

bluesnake

Think the first one is to disconnect the battery from the car overnight - could be a bad batch?

I would get a sensitive digital volt meter and find the longest cable going to the battery and measure the millivolts/microvolts dropped along it (the cable acts as a low ohm, series resistor) then start removing fuses, noting the voltage, then put the fuse back. higher the voltage, more current is being drawn.

You can use it in amp mode (parallel) but if you shorten something out, you may blow the meter. If the meter is not sensitive enough and the cable too thick, you may have to use the amp mode anyway, but the surge may kill the meter

Perhaps get a few meters of 13amp cable to temporary lengthen either + or - select one of the 3 colours and connect it in series and this will create a larger resistor with a bigger volt drop. Do not start the car with this on.

SatanicHare

My mate had this problem a few years ago on his VW Passat, turned out to be an issue with his aftermarket car stereo, can't remember exactly what the problem was though, sorry.

sun-n-moon

Assuming that you have checked that the alternator is putting out enough charge, then yes check the stereo. I had this problem with a Cavalier. The culprit was the radio. If the radio was disconnected everything was fine but once it was connected it drained the battery overnight. never found out why but that was the problem.

forgotmyname

Alternator.

Its feeding back when not running. But as above a decent auto electrician will find the fault in no time.

Slowly_does_it..

Agree with above, my aftermarket radio used to turn on when the battery level dropped a bit - like the amount a normal battery drops after standing for 12 hours. I fixed mine by adding a manual switch. Good luck finding the reason!!

rubble2

I had a brand new Ford a few years ago now that had a fault from delivery similar to what you describe. It went back to the dealer and they found that the relay for the heated rear window was faulty causing it to be switched on permanently. Worth a check

sk240

It could be anything, you need to attach a multiplier inline (in series) with the live or neutral battery cable set to amp mode and pull fuses until the current stops.Then find out whats connected to that fuse to then narrow it down further.
This can take quite a long time to find though.
If its the alternator, you may need to remove the cable to it to confirm, or sometimes if you feel it and its warm (leave it a couple of hours after driving it) then you need a new alternator

thenudeone

As long as it always stays charged when driving, one solution is to fit a heavy duty battery discharge preventer which automatically cuts all the current from the battery when the voltage drops below a certain point.

eg:
http://www.ebay.co.uk/itm/CAR-BATTERY-GUARD-AUTOMATIC-SWITCH-DISCHARGE-PROTECTOR-/200664496217?pt=UK_Car_Accessories_Safety_Security&hash=item2eb8893859

http://www.noflatbatteries.com/

http://www.ebay.co.uk/itm/Battery-Guard-Classic-TypeI-Car-battery-protector-/220632614559#vi-content