Ping Mrcheerful

I don't know if this might be your area...

I am sometimes (read as very rarely) finding the battery completely flat when I try to start the car, sometimes it has only been left overnight and had been fine the previous day.

The car is not used regularly, but I'm certain it is not normal for it to go flat so quickly. For instance it was used on a good run out on Thursday, when I again tried to start it on the Saturday morning it was completely flat. I have just fitted a larger battery, but the old one has charged up fine and is holding its charge. The charging system is charging fine with a maximum load on.

Electrically and electronically it is a very complex car. The current drawn when first parked is about 300mA and as things shut down it gradually drops to about 20mA after 20minutes or so. It has done this reliably every time I have checked it, but obviously I cannot leave a 1amp maximum range meter in circuit as a fixture due to the starter load and other loads.

There are three feeds joining at the battery post - starter cable, near side fuse box and off side fuse box, but each of them is designed to source at least 100amps.

I've moved over to checking the voltage dropped across one of the feeds, but on standby the current is so slight it is almost immeasurable on the 200mV range - 0.2mV is what I'm seeing.

Have you any better ideas or suggestions for tracking down this problem?



--
Regards,
Harry (M1BYT) (L)
http://www.ukradioamateur.co.uk


.

Relevant Pages

  • jump leads and jump starting
    ... I am looking you buy some jump leads "just in case". ... why doesn't the same apply to the "good" car? ... ten minutes to charge the flat battery. ... During this time isn't the flat battery being charged by both cars? ...
    (uk.rec.cars.maintenance)
  • Re: Car Battery help needed.....please
    ... It was still starting the car reliably after eight years use. ... a price the car makers were willing to pay, ... My first car was bought in '62 and required a new battery. ... The only real load on a battery is the starting one. ...
    (uk.rec.cars.maintenance)
  • Battery goes flat quickly
    ... My car battery seems to go flat quickly. ... When I put the flat battery on the charger, ...
    (rec.autos.tech)
  • Re: does this work?
    ... should have probably read the handbook), I have no idea what would happen if the battery went flat; would I have been locked out? ... With so much dependent on the electrics I would hate to find myself in the situation of being locked out of my car on account of a flat battery. ... doobries with the buttons to lock and unlock a normal looking key which opens the doors and tailgate bit not the glove box (and a little simple plastic 'emergency' key that opens all doors and starts the engine, which beggers the question why do I need the avoer £100 fancy doofers if a bit of shaped placky will do the job? ...
    (uk.local.cumbria)
  • Re: Car Battery help needed.....please
    ... It's still the same technology, but the application of that technology has ... It was still starting the car reliably after eight years use. ... My first car was bought in '62 and required a new battery. ... The only real load on a battery is the starting one. ...
    (uk.rec.cars.maintenance)
Loading