Car dilemma

[badger]

Somebody sort me out please as my brain is spinning. Week or so ago flattened car battery having not shut the boot properly and left for couple of days. Friendly neighbour jump starts me and I drive round for a while to make sure it’s charged up. Next day drive into Wick but then did one short journey in Wick and it seemed reluctant to start second time so drove it home. Was advised battery still not fully charged so friendly neighbour comes out again with charger.


I had never charged this particular car battery before and he drives something different so we thought we’d be careful and do it by the book, i.e. handbook. Handbook tells you to disconnect the battery "charging the battery with the cables connected may damage the vehicle’s electrical system". Well we certainly don’t want to do that, do we? Not with all the computerised stuff cars have these days. So – we disconnect the battery, charge it up. Fine – until I then need to go out and car won’t respond to handset. Pressing button – nothing happens. Panic and phone garage where I bought it (local dealer). He says they never disconnect battery when charging as sometimes it can wipe the memory !! Also said I would have to take it in to be re-programmed. Wish now I had read the handbook a bit more as would have seen that I could re-programme but, as one does, I believed what I was told. Since their callout charge is pretty high I got the breakdown people to come over, telling them thought it would have to be taken away. Man came and started car – without code. How did he do that? Wouldn’t tell me.


Seems I’m in a no win situation here if I’m ever silly enough to flatten battery again. Do I disconnect or don’t I? It’s a Rover 25 BTW. Who to believe? :eek:

[j4bberw0ck]

Badger, the stuff about disconnecting the battery is basically to cover themselves. Engine management chips and other computery-type components can be damaged if there are voltage spikes or a reversed polarity but you should be OK charging with the leads connected so long as you connect in the right order and disconnect in the right order, and don't allow a short circuit.

The other problem with disconnecting batteries is very often the radio code - of course, as it's a theft-prevention device, the radio forgets its code if you remove power.

You'll sometimes see dealers and workshops plugging a battery into the cig lighter socket so keep power for those bits that need it, but I don't know if that'll work for all cars, or only those where the cig lighter circuit is live at all times (i.e. with the ignition off).

If the battery is having trouble holding charge (you seem to suggest that it was reluctant to start the car after a short journey - was the engine cold at restart?) the forced discharge may have damaged it if it was an old battery that was past its best anyway.

Go for a spin down the road - 20 miles out, 20 back, and don't be afraid to use some revs. That should get it topped up. If it doesn't, get the battery tested.

[Angela]

One Saturday I had to get the RAC out to get me started (my own fault, I'd not driven the car for a while) which they did, but advised me the battery was old and I should get a new one straight away.

Drove around trying to find a new battery, remembering not to turn engine off as I did so...but no battery to be had locally, an unusual model apparently. Gave up and returned home. Battery flat again by the evening.

Over the weekend, phoned around and found a more distant source for a battery on the Monday. RAC came out again and re-started the car....off I drove and got the battery. Hurrah!

Then waited for some time in a very cold car for someone to come and fit it (very silly me, I thought they were going to do that for me).

Once the new battery was installed, everything worked except for the radio.
Thankfully I had the code ...conveniently in the glove compartment...yes, that was a really safe place to leave it, wasn't it? :lol:

Happy ending....but made me realise how little I knew about my car and how ill-prepared I was to deal with problems....:(

[badger]

Thanks both of you. I've been assured by garage that battery is fine, just wasn't fully charged even after charging it. It seems Ok now and I've given it lots of runs but it has made me wary. And a bit annoyed that I wasn't told I could re-program - know better now.

Would you not think with all the wonders of modern science we could have advanced beyond all this. I'm sure all the computerised bits of cars are amazing, together with all the entertainment bells and whistles, but sometimes think the old cars were a lot simpler. I can remember taking the spark plugs out and rubbing them with a pencil if the car didn't want to start on a cold morning. Happy days.

Bit like computers before Windows. Maybe not so versatile but used to enjoy typing in DOS commands and feeling in charge. Now it's the PC that bosses me about.

[j4bberw0ck]

I used to build cars as a hobby in the 70's; mostly Ford Escorts for club rallying. I'd start with all the bits and build from the ground up, including rewiring to non-standard specifications. So, once upon a time I was pretty confident of being able to do just about anything on just about any car.

These days, I open the bonnet, check the oil, and shut it again. I haven't got a scoobie about all the rest of it - black boxes everywhere, servicing by plugging into a computer for diagnosis across the internet....... but it has to be said that if you want good mpg and low emissions, there's little option.

[Angela]

My dad was a young vet way back in the 1940s...my mum used to accompany him on "home visits" to give him a hand (so to speak) with the calving or whatever :eek:

Her other job was cranking up the car as and when required!:lol:

[badger]

Didn't even have to take a driving test in those days. My father had a motor bike when he was young so when he finally got a car, some years later, he just drove around a local field and that was that. Used to put a lamp in the engine in winter to stop it freezing.

Think most people now don't DIY with cars - so little you can do. Maybe that's why garages like to make it all sound mysterious.