Battery Life

[Nemo]

A few days ago we saw a TV programme which showed a man in the UK going to pick up his car which had been left in a car park for ten weeks. It started first time!

Ever since OH and myself have been debating if this was real. The car was medium sized and looked fairly modern.

Is this possible or is it likely that it was staged.

[swill453]

A few days ago we saw a TV programme which showed a man in the UK going to pick up his car which had been left in a car park for ten weeks. It started first time!

Ever since OH and myself have been debating if this was real. The car was medium sized and looked fairly modern.

Is this possible or is it likely that it was staged.

I don't see why not. I regularly leave my car at home for six or seven week trips away, and it always starts first time when I get back.

Scott.

[Tedx]

Mine was not driven/started for months from March 2020.....

[Mike4]

It typically takes around 1AH of energy to start an ICE.

Given yer average starter battery is in the order of 60AH capacity, one engine start is pretty un-challenging for a young battery in good condition.

As they grow older they sulphate and lose capacity. When they get down to a few AH of capacity they start letting you down and you'll probably buy a new one. (After giving it a good charge-up and finding it made no difference!)

[bungeejumper]

We're forgetting that some parts of the car will have been drawing current for the full ten weeks. Not least, the intruder alarm, or the gizmo that listens out for the familiar presence of your key fob. (Which may or may not be the same thing.)

But even so, ten weeks ought to be a doddle for a tolerably recent battery. I'd have been disappointed if a three year old battery couldn't get it started.

BJ

[MyNameIsUrl]

On my car the 'gizmo that listens out for the familiar presence of your key fob' switches off after about 3 weeks to save the battery. The way to reactivate it is to unclip a cover on the key fob which reveals a metal key which you insert into a hole in the car door just below the handle and twist. Simple if you know, but I imagine there are a lot of AA callouts at airport carparks from people who have just returned from a month away.

[bungeejumper]

On my car the 'gizmo that listens out for the familiar presence of your key fob' switches off after about 3 weeks to save the battery. The way to reactivate it is to unclip a cover on the key fob which reveals a metal key which you insert into a hole in the car door just below the handle and twist.

Oh, how ingenious. Whatever will they think of next? But where to find the hole?

Surely you can't be suggesting that I should poke around the pristine paintwork under my door handle with a screwdriver, until I find a piece of bendy plastic and then snap it off ? Good lord, I'm getting an attack of the vapours just from thinking about it.

The Mk1 Rover 200 series (of which I had an early example) had a much neater solution to this dilemma. Under one of the rear wheel arches was a pair of wires on a screw-fitting connector block. And all you had to do was push a bent pin into the connector, and hurrah, all the doors would magically unlock. I am constantly astounded that this world-beating British idea never found the popularity it deserved.

BJ

[MyNameIsUrl]

Oh, how ingenious. Whatever will they think of next? But where to find the hole?

Surely you can't be suggesting that I should poke around the pristine paintwork under my door handle with a screwdriver, until I find a piece of bendy plastic and then snap it off ? Good lord, I'm getting an attack of the vapours just from thinking about it.

On some cars the hole is actually in the doorhandle itself. It's not difficult to find. I used to use it every time I locked or unlocked my car until the key fob was invented.

[Nemo]

Thanks everyone. This has resolved an ongoing discussion between me and the OH - looks like I lost

[Mike4]

Thanks everyone. This has resolved an ongoing discussion between me and the OH - looks like I lost

Noooo!!!!

You simply came second. Which is almost as good as winning!

Err...

[airbus330]

FWIW I worked aboard for 3 months in the winter for several years and my BMW's never failed to start on my return. TBH this did surprise me at the time. I put it down to the Stop Start batteries being bigger, but no proof of that helping.

[scrumpyjack]

My wife's sister frequently leaves her car unused for months. She leaves a solar trickle charger in it and has never had a problem

[gryffron]

My current car battery only lasts about six weeks without use. New battery but the car is quite old (2010) and has an alarm. I suspect this was a time when alarms were quite a battery drain. During lockdown I plugged it into a motorcycle trickle charger, which kept it fine.

35 years ago I was a student in Sheffield, my then car (an Avenger) sat buried under a snowdrift for 10 weeks. Started straight away when the snow melted. No alarm, keyfobs, not so much as a clock back then of course. So off was really off.

The EU has had a huge push in recent decades on suspend mode power usage of consumer electrics. Regardless of whether we follow the regulations or not, this resulted in very very low power usage of many modern chip designs. Modern electronics, I would have thought would be such a trickle as to barely notice. I wouldn't be at all surprised to hear the battery self-discharge from a lead-acid battery is more than the usage of today's alarm/sensors. I know for a fact the keyfob sensor would run for decades on a 60Ah battery, because I have programmed the same chip for other applications.

So I would say entirely possible. Although there was a window when battery life was less, not so today. Maybe you're remembering that window. Or maybe your car is from those days too.

Gryff

[tjh290633]

My current car battery only lasts about six weeks without use. New battery but the car is quite old (2010) and has an alarm. I suspect this was a time when alarms were quite a battery drain. During lockdown I plugged it into a motorcycle trickle charger, which kept it fine.

35 years ago I was a student in Sheffield, my then car (an Avenger) sat buried under a snowdrift for 10 weeks. Started straight away when the snow melted. No alarm, keyfobs, not so much as a clock back then of course. So off was really off.

The EU has had a huge push in recent decades on suspend mode power usage of consumer electrics. Regardless of whether we follow the regulations or not, this resulted in very very low power usage of many modern chip designs. Modern electronics, I would have thought would be such a trickle as to barely notice. I wouldn't be at all surprised to hear the battery self-discharge from a lead-acid battery is more than the usage of today's alarm/sensors. I know for a fact the keyfob sensor would run for decades on a 60Ah battery, because I have programmed the same chip for other applications.

So I would say entirely possible. Although there was a window when battery life was less, not so today. Maybe you're remembering that window. Or maybe your car is from those days too.

Gryff

I was in Sheffield in the late 1950s, when we had some severe weather. Initially I had an old GPO Telephone van, which had the benefit of a starting handle. Soon replaced in 1958 by a VW beetle, with a 6 volt battery. Despite being dug out from the snow, it was a reliable starter. Back then batteries came with a 2 year guarantee, but you could expect them to expire in the 25th month or soon after. That existed for a couple of decades at least. It's some time since I had to replace a battery, despite alarms, clocks and other paraphernalia. We tend to keep our second cars for a long time. The current one is about 14 years old. It's on its second battery. Somebody removed the built-in obsolescence.

TJH

[Lanark]

On my old 2CV, turning on the radio would noticeably dim the headlights, so when driving at night you had a choice between listening to some music or being able to see where you were going.
They don't make them like that any more!

[didds]

Thanks everyone. This has resolved an ongoing discussion between me and the OH - looks like I lost

Noooo!!!!

You simply came second. Which is almost as good as winning!

Err...

And the OH came second from last!

[bungeejumper]

On my old 2CV, turning on the radio would noticeably dim the headlights, so when driving at night you had a choice between listening to some music or being able to see where you were going.

You had a radio in your 2CV? How long did the valves last?

Luxury! In our 1972 Fiat 500 the in-car entertainment was that we had to sit and play I-Spy. And if it rained, we had to open the sunroof and lean out, in order to clear the water off the windscreen with a squeegee. But tell that to kids these days, and....

Seriously, many 2CVs had 6 volt batteries. I see that you can still get them, if you've got eighty quid rattling around in your pocket.

BJ

[Watis]

On my old 2CV, turning on the radio would noticeably dim the headlights, so when driving at night you had a choice between listening to some music or being able to see where you were going.

You had a radio in your 2CV? How long did the valves last?

Luxury! In our 1972 Fiat 500 the in-car entertainment was that we had to sit and play I-Spy. And if it rained, we had to open the sunroof and lean out, in order to clear the water off the windscreen with a squeegee. But tell that to kids these days, and....

Seriously, many 2CVs had 6 volt batteries. I see that you can still get them, if you've got eighty quid rattling around in your pocket.

BJ

In my youth I had a car with a valve radio - they did exist!

And, when turning off the windscreen wipers in my first car, you had to time the operation of the off switch with the wipers being at the bottom of their sweep - no self-park in those days!

Watis

[Mike4]

And, when turning off the windscreen wipers in my first car, you had to time the operation of the off switch with the wipers being at the bottom of their sweep - no self-park in those days!

Watis

Yep, I remember that too. Certainly had to do that with my first car an Austin A35. And pretty sure the same applied to my first 10 or 12 Minis, up until about 1968.

The indicators (also a luxury) on the A35 weren't 'self-cancelling' either!

[ReformedCharacter]

Seriously, many 2CVs had 6 volt batteries. I see that you can still get them, if you've got eighty quid rattling around in your pocket.

BJ

They did indeed, one of my friends had one, a 2CV van with a 435cc engine. On the return from a trip to Cornwall with 4 of us aboard we took a scenic route at night. It became my turn to drive a stint but after a few miles I admitted to my pals that I could hardly see anything at all in front of the vehicle, well my eyesight wasn't perfect but neither were the lights. Someone braver - or more foolish - took the wheel. Early 2CVs also had wipers that were driven via the gearbox and consequently stopped when you were stationary in traffic. A friend was driving one in London when snow was falling heavily and was stationary in traffic. A passing policeman asked him why he was driving without working wipers and my friend said 'They do work when the car is moving, you can run along beside me when the traffic moves, just to make sure'

RC