Charging in car

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Scott

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Jun 12, 2022, 12:33:15 PMJun 12
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I want to be able to charge my Pixel 5 phone (USB-C) in the car in
emergencies. I looked at the Internet for charging cables and saw all
sorts of contradictory advice: charging in the car will damage the
phone, there is no problem at all with charging in the car, the car
battery will be flattened, fast charging is impossible.

I bought a Belkin twin USB-C and USB-A car charger. I have tested
this and 'rapid charging' is enabled. The TomTom works at the same
time. Can I assume this will not cause any issues with the phone?
Also, if I plug the TomTom into the USB-A outlet, could this provide
excess current and damage the TomTom or are all these chargers
compatible?

Andy Burns

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Jun 12, 2022, 12:45:05 PMJun 12
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Scott wrote:

> I want to be able to charge my Pixel 5 phone (USB-C) in the car in
> emergencies. I looked at the Internet for charging cables and saw all
> sorts of contradictory advice: charging in the car will damage the
> phone, there is no problem at all with charging in the car, the car
> battery will be flattened, fast charging is impossible.
>
> I bought a Belkin twin USB-C and USB-A car charger. I have tested
> this and 'rapid charging' is enabled. The TomTom works at the same
> time. Can I assume this will not cause any issues with the phone?

Yes.


Scott

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Jun 13, 2022, 3:49:46 AMJun 13
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On Sun, 12 Jun 2022 17:45:01 +0100, Andy Burns <use...@andyburns.uk>
wrote:
Thanks.

Martin Brown

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Jun 13, 2022, 6:43:02 AMJun 13
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If it is an expensive phone then I wouldn't really want to have it
plugged into a charger when the starter motor is used. That said modern
cars now do hot restarts once the engine is warm and I have never had
any problems. The only one I have run into is that a normal car charger
port cannot negotiate Apple fast charge protocol and at its safe and low
default charge rate fails to get a flat iPhone going at all.

We discovered this when Northern Powergrid knackered the electricity
supply to most of the North for best part of a week last December.

--
Regards,
Martin Brown

Theo

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Jun 13, 2022, 7:37:38 AMJun 13
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Martin Brown <'''newspam'''@nonad.co.uk> wrote:
> If it is an expensive phone then I wouldn't really want to have it
> plugged into a charger when the starter motor is used.

If the charger adapter is any good, it should be able to handle voltage
dropouts like that. It only needs to provide 5v, and I hope your battery
voltage is not dropping that far.

A decent adapter should also filter the EMI, although I suppose there are
non-decent ones out there. Stick with a reputable brand if you're unsure.

> The only one I have run into is that a normal car charger port cannot
> negotiate Apple fast charge protocol and at its safe and low default
> charge rate fails to get a flat iPhone going at all.

Depends on the age of the car: some cars with USB ports only have them as a
way of adding files to the music system and/or firmware updates, which means
they're only rated at 500mA. You can charge a phone from that, but very
slowly, and if the phone is on at the time it may gradually lose charge
(especially if doing satnav or similar). I had this problem in a 2019
US-spec Yaris (a rebrand of a Mazda 2), so even non-ancient cars are
affected.

It's much better to buy a cigarette-lighter charger, since you get fast
charging protocols and they are easy to replace eg if you want to switch
from USB-A to USB-C, or you get a different phone with different flavour of
fast charging.

For example, an unexpected benefit of buying a USB-C car charger is I can
also charge my laptop from it (slowly).

Theo

Martin Brown

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Jun 13, 2022, 8:18:40 AMJun 13
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On 13/06/2022 12:37, Theo wrote:
> Martin Brown <'''newspam'''@nonad.co.uk> wrote:
>> If it is an expensive phone then I wouldn't really want to have it
>> plugged into a charger when the starter motor is used.
>
> If the charger adapter is any good, it should be able to handle voltage
> dropouts like that. It only needs to provide 5v, and I hope your battery
> voltage is not dropping that far.

I'm more paranoid about the currents flowing and electrical spikes from
the near dead short instantaneous spike when it begins to turn over.
>
> A decent adapter should also filter the EMI, although I suppose there are
> non-decent ones out there. Stick with a reputable brand if you're unsure.
>
>> The only one I have run into is that a normal car charger port cannot
>> negotiate Apple fast charge protocol and at its safe and low default
>> charge rate fails to get a flat iPhone going at all.
>
> Depends on the age of the car: some cars with USB ports only have them as a
> way of adding files to the music system and/or firmware updates, which means
> they're only rated at 500mA. You can charge a phone from that, but very
> slowly, and if the phone is on at the time it may gradually lose charge
> (especially if doing satnav or similar). I had this problem in a 2019
> US-spec Yaris (a rebrand of a Mazda 2), so even non-ancient cars are
> affected.
>
> It's much better to buy a cigarette-lighter charger, since you get fast
> charging protocols and they are easy to replace eg if you want to switch
> from USB-A to USB-C, or you get a different phone with different flavour of
> fast charging.
>
> For example, an unexpected benefit of buying a USB-C car charger is I can
> also charge my laptop from it (slowly).

It is the sort of annoying thing that you only find out in an emergency.
Most of the time it recharges the iPhone just fine so long as the phone
already has enough charge in it to negotiate a faster rate.


--
Regards,
Martin Brown

Java Jive

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Jun 13, 2022, 8:24:45 AMJun 13
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Despite others' replies up to this point, all of which I've read, I have
to report that trying to keep my tablet charged via the USB socket of my
Skoda Fabia doesn't really work reliably. Without any warning, after
some distance, I find the tablet turning off, and when I examine why, I
find that its battery is completely exhausted, despite it having been
plugged into the USB socket all the while the car was moving.

I seem to get better results from the cigarette lighter adaptor that I
used with previous cars that had no USB socket.

Worse still, I copied a load of music onto my tablet to have something
to listen to on a recent long trip to a family do, but could not get the
car to recognise the tablet as a storage device.

So for me, it has to be tablet, for the Navigation app, connected to the
cigarette lighter socket, and a USB stick in the USB socket, which seems
unnecessarily retro.

--

Fake news kills!

I may be contacted via the contact address given on my website:
www.macfh.co.uk

Mark Carver

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Jun 13, 2022, 8:45:20 AMJun 13
to
On 13/06/2022 13:18, Martin Brown wrote:
> On 13/06/2022 12:37, Theo wrote:
>> Martin Brown <'''newspam'''@nonad.co.uk> wrote:
>>> If it is an expensive phone then I wouldn't really want to have it
>>> plugged into a charger when the starter motor is used.
>>
>> If the charger adapter is any good, it should be able to handle voltage
>> dropouts like that.  It only needs to provide 5v, and I hope your
>> battery
>> voltage is not dropping that far.
>
> I'm more paranoid about the currents flowing and electrical spikes
> from the near dead short instantaneous spike when it begins to turn over.

Motor cars are full of their own electronics, and have been for decades
now, I've never seen any evidence that spikes from starting the engine
are a particular problem ?

I do remember getting Alternator 'Whine' when I fitted a cassette player
in my old banger in the 80s though.

Peter Johnson

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Jun 13, 2022, 1:35:42 PMJun 13
to
On Mon, 13 Jun 2022 13:24:38 +0100, Java Jive <ja...@evij.com.invalid>
wrote:


>
>Despite others' replies up to this point, all of which I've read, I have
>to report that trying to keep my tablet charged via the USB socket of my
>Skoda Fabia doesn't really work reliably. Without any warning, after
>some distance, I find the tablet turning off, and when I examine why, I
>find that its battery is completely exhausted, despite it having been
>plugged into the USB socket all the while the car was moving.
>
>I seem to get better results from the cigarette lighter adaptor that I
>used with previous cars that had no USB socket.
>
The Toyotas that I've had over the last ten years or so all had (have
in the case of the current car) wirefree charging but the older ones
weren't very good at it. The last car and the current one are.
But I have a cooler box that plugs into a cigar lighter barely kept
the contents cool in the older cars but they get properly cold in the
last and the current one, which tells me that they are putting more
amps down the lighter circuit because of people wanting to charge
phones and tablets. Same probably applies to the USB sockets and the
wirefree charger.

Chris Green

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Jun 13, 2022, 4:18:05 PMJun 13
to
You can't really "put more amps" down a circuit. Unless the voltage
drops ridiculously when you load it the current is determined almost
totally by the load. A 12 volt socket is a 12 volt socket and only if
you blow the fuse will anything really change.

--
Chris Green
·

Theo

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Jun 13, 2022, 4:51:22 PMJun 13
to
Java Jive <ja...@evij.com.invalid> wrote:
> Despite others' replies up to this point, all of which I've read, I have
> to report that trying to keep my tablet charged via the USB socket of my
> Skoda Fabia doesn't really work reliably. Without any warning, after
> some distance, I find the tablet turning off, and when I examine why, I
> find that its battery is completely exhausted, despite it having been
> plugged into the USB socket all the while the car was moving.

If you leave the tablet turned on, ie don't shut it down, it's possible you
aren't running the engine long enough to give it much charge. eg if you
drive for half an hour, if the USB socket is only giving it 500mA, it's only
received 250mAh. The battery could be 5000mAh, so that's a topup of 5%.
Then if you leave the car parked for a few hours it'll run down that charge.
Eventually it'll run down the battery enough to turn off, but then the car
won't charge it very much next time.

This is especially bad if you have location and mobile data turned on - the
tablet may be chatting to Google/etc, which eats the meagre charge you
received.

It's why a fast charger makes more sense in a car than many other places,
because you often only spend short periods in the car and you engage in heavy
battery-draining activities (satnav, music streaming) while doing so.

> I seem to get better results from the cigarette lighter adaptor that I
> used with previous cars that had no USB socket.
>
> Worse still, I copied a load of music onto my tablet to have something
> to listen to on a recent long trip to a family do, but could not get the
> car to recognise the tablet as a storage device.

The car is probably expecting a USB Mass Storage device, ie a USB stick.
The tablet probably doesn't present as that - Androids are usually PTP or
MTP, while I'm not sure if iPads do anything except iTunes.

(Android 2 and 3 supported USB Mass Storage, so there are old guides
floating around about how to enable it, but they don't work on modern
tablets. The problem is you had to unmount the storage from the tablet
before the computer could see it, which is awkward for anything the tablet
wants to use)

I'm not sure if there's a workaround to make an Android export Mass Storage
for a subset of files - maybe there is if you're rooted.

> So for me, it has to be tablet, for the Navigation app, connected to the
> cigarette lighter socket, and a USB stick in the USB socket, which seems
> unnecessarily retro.

Try playing music from the tablet and connecting to the sound system via
Bluetooth?

Theo

Andy Burns

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Jun 13, 2022, 6:22:14 PMJun 13
to
Martin Brown wrote:

> Andy Burns wrote:
>
>> Scott wrote:
>>
>>> Can I assume this will not cause any issues with the phone?
>>
>> Yes.
>
> If it is an expensive phone then I wouldn't really want to have it plugged into
> a charger when the starter motor is used.

Why? It's a *CAR* charger, it's from a reasonable name brand, it knows there
are going to be voltage transients, it'll be designed for that, they provide a
£1500 connected equipment guarantee.

<https://www.belkin.com/uk/support-article?articleNum=291992>

Scott

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Jun 14, 2022, 5:03:57 AMJun 14
to
On Mon, 13 Jun 2022 23:22:11 +0100, Andy Burns <use...@andyburns.uk>
wrote:
Thanks for all the comments. This fits in with my line of thinking.

Another question: I have connected the TomTom to the USB-A port. When
the engine is started the TomTom momentarily shuts down then restarts.
It does not do this with the TomTom charger. Is this because the
Belkin charger is providing extra protection or because the TomTom
charger is more suitable? (Should I use the Belkin charger all the
time or only when needed for the phone?)

Java Jive

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Jun 14, 2022, 9:42:56 AMJun 14
to
Tx Theo, see below ...

On 13/06/2022 21:51, Theo wrote:
>
> Java Jive <ja...@evij.com.invalid> wrote:
>>
>> Despite others' replies up to this point, all of which I've read, I have
>> to report that trying to keep my tablet charged via the USB socket of my
>> Skoda Fabia doesn't really work reliably. Without any warning, after
>> some distance, I find the tablet turning off, and when I examine why, I
>> find that its battery is completely exhausted, despite it having been
>> plugged into the USB socket all the while the car was moving.
>
> If you leave the tablet turned on, ie don't shut it down, it's possible you
> aren't running the engine long enough to give it much charge.

No, as described above, I found it kept running down and switched itself
off no matter how long I had been travelling in the car. I made my
first long journey, about 700 miles, a couple of weeks back, and it
still ran down and switched itself off.

>> I seem to get better results from the cigarette lighter adaptor that I
>> used with previous cars that had no USB socket.
>>
>> Worse still, I copied a load of music onto my tablet to have something
>> to listen to on a recent long trip to a family do, but could not get the
>> car to recognise the tablet as a storage device.
>
> The car is probably expecting a USB Mass Storage device, ie a USB stick.
> The tablet probably doesn't present as that - Androids are usually PTP or
> MTP, while I'm not sure if iPads do anything except iTunes.
>
> (Android 2 and 3 supported USB Mass Storage, so there are old guides
> floating around about how to enable it, but they don't work on modern
> tablets. The problem is you had to unmount the storage from the tablet
> before the computer could see it, which is awkward for anything the tablet
> wants to use)
>
> I'm not sure if there's a workaround to make an Android export Mass Storage
> for a subset of files - maybe there is if you're rooted.

Maybe I have to install some sort of Android auto app, I haven't
investigated that yet.

>> So for me, it has to be tablet, for the Navigation app, connected to the
>> cigarette lighter socket, and a USB stick in the USB socket, which seems
>> unnecessarily retro.
>
> Try playing music from the tablet and connecting to the sound system via
> Bluetooth?

Don't really want to do that, because:

:-( I found the phone of the car's previous owner on the system, and
could only make it forget their phone by resetting the system back to
factory defaults.

:-( I don't know how much personal data the car may be feeding back
to the manufacturer.

https://www.seattletimes.com/business/what-does-your-car-know-about-you-we-hacked-a-chevy-to-find-out/

I don't want my own phone's details to be permanently on such a system
even when I don't need to connect it.

Peter Johnson

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Jun 14, 2022, 12:11:55 PMJun 14
to
On Mon, 13 Jun 2022 21:16:34 +0100, Chris Green <c...@isbd.net> wrote:


>> >
>> The Toyotas that I've had over the last ten years or so all had (have
>> in the case of the current car) wirefree charging but the older ones
>> weren't very good at it. The last car and the current one are.
>> But I have a cooler box that plugs into a cigar lighter barely kept
>> the contents cool in the older cars but they get properly cold in the
>> last and the current one, which tells me that they are putting more
>> amps down the lighter circuit because of people wanting to charge
>> phones and tablets. Same probably applies to the USB sockets and the
>> wirefree charger.
>
>You can't really "put more amps" down a circuit. Unless the voltage
>drops ridiculously when you load it the current is determined almost
>totally by the load. A 12 volt socket is a 12 volt socket and only if
>you blow the fuse will anything really change.

OK. I'm typing nonsense. But the latest cars must have more output on
the lighter circuits otherwise how could the (same) cooler box be
colder?

David Woolley

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Jun 14, 2022, 4:43:22 PMJun 14
to
On 14/06/2022 17:11, Peter Johnson wrote:
> OK. I'm typing nonsense. But the latest cars must have more output on
> the lighter circuits otherwise how could the (same) cooler box be
> colder?

Even now, I believe the only current limit on cars is a fuse, which
limits current by cutting it off suddenly and permanently.

Assuming that both vehicles were nominally 12 volts, the only reasons
there might be a difference are that the voltage might be slightly
higher, but I'd hope that didn't make a big difference, or the wiring in
the old one was of poor quality, and there was a large voltage drop in
the wiring, or the socket.

It doesn't look like a typical 50W Peltier cooler is going to overstress
a normal cigarette socket (although it might overstress an earlier
accessory socket), and the the effect of battery voltage changes over
the normal battery range shouldn't be that great (the current changes
faster than linearly, but the extra cooling varies less than linearly
with current.

Andy Burns

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Jun 15, 2022, 2:22:30 AMJun 15
to

Java Jive wrote:

> trying to keep my tablet charged via the USB socket of my Skoda Fabia doesn't
> really work reliably. Without any warning, after some distance, I find the
> tablet turning off, and when I examine why, I find that its battery is
> completely exhausted, despite it having been plugged into the USB socket all
> the while the car was moving.

Yes GPS can be power-hungry.

How much current would the tablet like for 'rapid' charging? How much current
will the car's USB socket supply? Maybe a cigar lighter USB charger can provide
more current ...


Andy Burns

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Jun 15, 2022, 2:27:32 AMJun 15
to

Peter Johnson wrote:

> The last car and the current one are. But I have a cooler box that plugs into
> a cigar lighter barely kept the contents cool in the older cars but they get
> properly cold in the last and the current one, which tells me that they are
> putting more amps down the lighter circuit

The car doesn't push amps, the cooler pulls them.

They may fit thicker wire to reduce voltage drop, do newer toyotas now use
Silver/Calcium batteries like fords, at a slightly higher voltage?

Andy Burns

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Jun 15, 2022, 2:36:41 AMJun 15
to
Theo wrote:

> It's why a fast charger makes more sense in a car than many other places,
> because you often only spend short periods in the car and you engage in heavy
> battery-draining activities (satnav, music streaming) while doing so

I have a 65W charger in my car (tiny thing, matchbox size) which can run/charge
any of my USB-C devices.

tony sayer

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Jun 20, 2022, 3:04:25 PMJun 20
to
In article <t874bi$ndg$1...@gioia.aioe.org>, Martin Brown
<'''newspam'''@nonad.co.uk> scribeth thus
Very poor design not to be able to cope with that!, got a 4 way USB
adapter in my car, many differing phones have been and are charged in
that as well as it running the PURE add on DAB radio!..
--
Tony Sayer


Man is least himself when he talks in his own person.

Give him a keyboard, and he will reveal himself.


Martin Brown

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Jul 6, 2022, 3:46:47 AMJul 6
to
On 14/06/2022 14:42, Java Jive wrote:
> Tx Theo, see below ...
>
> On 13/06/2022 21:51, Theo wrote:
>>
>> Java Jive <ja...@evij.com.invalid> wrote:
>>>
>>> Despite others' replies up to this point, all of which I've read, I have
>>> to report that trying to keep my tablet charged via the USB socket of my
>>> Skoda Fabia doesn't really work reliably.  Without any warning, after
>>> some distance, I find the tablet turning off, and when I examine why, I
>>> find that its battery is completely exhausted, despite it having been
>>> plugged into the USB socket all the while the car was moving.
>>
>> If you leave the tablet turned on, ie don't shut it down, it's
>> possible you
>> aren't running the engine long enough to give it much charge.
>
> No, as described above, I found it kept running down and switched itself
> off no matter how long I had been travelling in the car.  I made my
> first long journey, about 700 miles, a couple of weeks back, and it
> still ran down and switched itself off.

There is something wrong with the charger, the lead or the tablet then.
Try another charging lead and another plug in charger.

I suspect the "Charging" icon does not appear on the device.
(or it issues a slow charging warning because it cannot negotiate a
sufficiently fast charge rate - though it must be a brute then)

The only problem I have ever seen with operating one in car has been
that the car won't negotiate Apple fast charge protocol with a
completely dead iPhone/Pad and so once flat it stays flat forever.

Otherwise it works fine provided that the device that it is trying to
charge is not completely stone dead.
Pairing with your own vehicle also gives the phone access to a better
external antenna (handy in bad signal rural areas like mine) and full
hands free operation.

You can delete the bluetooth pairing info later if you are sufficiently
paranoid.

--
Regards,
Martin Brown

Andy Burns

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Jul 6, 2022, 4:08:10 AMJul 6
to
Martin Brown wrote:

> On 14/06/2022 14:42, Java Jive wrote:
>> Tx Theo, see below ...
>>
>> On 13/06/2022 21:51, Theo wrote:
>>>
>>> Java Jive <ja...@evij.com.invalid> wrote:
>>>>
>>>> Despite others' replies up to this point, all of which I've read, I have
>>>> to report that trying to keep my tablet charged via the USB socket of my
>>>> Skoda Fabia doesn't really work reliably.  Without any warning, after
>>>> some distance, I find the tablet turning off, and when I examine why, I
>>>> find that its battery is completely exhausted, despite it having been
>>>> plugged into the USB socket all the while the car was moving.
>>>
>>> If you leave the tablet turned on, ie don't shut it down, it's possible you
>>> aren't running the engine long enough to give it much charge.
>>
>> No, as described above, I found it kept running down and switched itself off
>> no matter how long I had been travelling in the car.  I made my first long
>> journey, about 700 miles, a couple of weeks back, and it still ran down and
>> switched itself off.
>
> There is something wrong with the charger, the lead or the tablet then.
> Try another charging lead and another plug in charger.

Does the tablet say "Charging rapidly"? If not, it might only be getting 500mA
and GPS+4G+screen can easily suck more than that.


Scott

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Jul 6, 2022, 4:42:03 AMJul 6
to
On Tue, 14 Jun 2022 10:03:54 +0100, Scott
<newsg...@gefion.myzen.co.uk> wrote:
[snip]
>
>Another question: I have connected the TomTom to the USB-A port. When
>the engine is started the TomTom momentarily shuts down then restarts.
>It does not do this with the TomTom charger. Is this because the
>Belkin charger is providing extra protection or because the TomTom
>charger is more suitable? (Should I use the Belkin charger all the
>time or only when needed for the phone?)

This is continuing. I am wondering if this is a good thing, offering
added protection to the TomTom, or if I should be trying to avoid it
(by using the original charger when possible). I suspect the Belkin
unit is better quality than the supplied charger. .

Martin Brown

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Jul 6, 2022, 5:45:43 AMJul 6
to
On 14/06/2022 17:11, Peter Johnson wrote:
What you say makes no sense at all.

The old style resistive cigarette lighter would draw something like
10-15A for a short time to get the lighter mesh *glowing red hot*.
I doubt if any cooler box draws half that current.

And modern chargers draw much less than that probably about 2A @ 14v.

The only thing I can think of that might make a difference is if the old
vehicle had the wrong sort of 15A fuse fitted on that circuit or an aged
clapped out battery with a poxy output voltage under modest load.

Automotive fuses should be low voltage drop otherwise you lose a chunk
of the power delivered to the load in the fuse itself.

--
Regards,
Martin Brown

Martin Brown

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Jul 6, 2022, 7:15:27 AMJul 6
to
On 15/06/2022 07:22, Andy Burns wrote:
>
> Java Jive wrote:
>
>> trying to keep my tablet charged via the USB socket of my Skoda Fabia
>> doesn't
>> really work reliably.  Without any warning, after some distance, I
>> find the
>> tablet turning off, and when I examine why, I find that its battery is
>> completely exhausted, despite it having been plugged into the USB
>> socket all
>> the while the car was moving.
>
> Yes GPS can be power-hungry.

It shouldn't really be in a decent implementation today though.
>
> How much current would the tablet like for 'rapid' charging?  How much
> current will the car's USB socket supply?  Maybe a cigar lighter USB
> charger can provide more current ...
>
>


--
Regards,
Martin Brown
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