Battery maintainer for reflashing ecu's, reprogramming keys

[robbocop33]

Looking for something that will keep a car battery charged steadily at around 12.5 to 14 volts while reprogramming an ecu, and while programming key fobs etc.
I've seen some really cheap ones claiming firstly to be 'battery chargers' and secondly also maintainers? But are they genuinely maintainers or are they maybe just calling a 'trickle charge' 'maintaining?
I mean i have a good battery charger already, would setting mine to trickle charge work? Thanks.

Edited by robbocop33 on Wednesday 24th July 09:09

[E-bmw]

Yes, just use what you have, nothing extra needed then.

[robbocop33]

Ok, just the stability thing that worried me, didn't know how stable normal battery chargers are, thought maintainers were bought for just that purpose mainly alone.

[Coilspring]

robbocop33 said:

Ok, just the stability thing that worried me, didn't know how stable normal battery chargers are, thought maintainers were bought for just that purpose mainly alone.

Test it?

Put the charger on , with a voltmeter. See what it does?

[E-bmw]

They both work on the same circuitry inside it is just the control of the current that differs, it will be stable with load on just fine.

In fact you may well find it is more stable as maintainers switch between different charge/maintenance rates as required whereas a charger just supplies current at 14.5 (FAS) volts on an as required basis.

[Penelope Stopit]

I have never had a problem flashing in-car ECU's while they are powered by their own good battery. At a guess the number of ECU's I have flashed is approximately 300 but could be many more

[Chris32345]

12v lithium jump pack connected up if you have any concerns about the battery in the car

[robbocop33]

Chris32345 said:

12v lithium jump pack connected up if you have any concerns about the battery in the car

I was going to go for a lithium charged Noco g7200, i have one of their emergency battery boosters and it's great.

[Penelope Stopit]

Why bother? If the vehicles battery is not up to it fit a new one

The mind boggles

[robbocop33]

Penelope Stopit said:

Why bother? If the vehicles battery is not up to it fit a new one

The mind boggles

Yes, sorry for my mind boggling stupidity, battery is brand new incidentally, i was clever enough to manage to buy one all on my own, it was quite difficult though! People have said you need a good steady supply to cope if say a 30 amp radiator fan kicks in etc while flashing an ecu in particular, i'll ignore those particulary mind boggling stupid real life testimonies though, facilitating the need for a steady voltage supply.

[Krikkit]

I'd be tempted to have a spare battery and a trickle charger connected to give it all a boost if it's going to be a problem if you get some transient dips under loads like that.

[Penelope Stopit]

robbocop33 said:

Penelope Stopit said:

Why bother? If the vehicles battery is not up to it fit a new one

The mind boggles

Yes, sorry for my mind boggling stupidity, battery is brand new incidentally, i was clever enough to manage to buy one all on my own, it was quite difficult though! People have said you need a good steady supply to cope if say a 30 amp radiator fan kicks in etc while flashing an ecu in particular, i'll ignore those particulary mind boggling stupid real life testimonies though, facilitating the need for a steady voltage supply.

I didn't comment you are stupid

As I've already mentioned, I've flashed hundreds of ECU's without a problem

The thing is none of the vehicles were running when I did the flashing, there was no chance of a cooling fan kicking in, a heated rear window switching on, headlights switching on or..............................

I'm very interested to know what vehicle ECU's you are flashing with the engine running

[robbocop33]

Penelope Stopit said:

I didn't comment you are stupid

As I've already mentioned, I've flashed hundreds of ECU's without a problem

The thing is none of the vehicles were running when I did the flashing, there was no chance of a cooling fan kicking in, a heated rear window switching on, headlights switching on or..............................

I'm very interested to know what vehicle ECU's you are flashing with the engine running

I didn't say i was going to flash an ecu with a car running? You want to know what vehicle's ecu im flashing with the engine running when i haven't said that's what i'm doing??Eh?
Anyway, back to reality, i'm using Renault can clip to code a spare key card in this instance. I tried hooking up my charger and at the battery it was showing 13 volts, which obviously isn't enough for this application as low voltage warning came up.
I've got a maintainer ordered now anyway.

[melhookv12]

Just to even things out.
Jaguar actually supply a battery maintainer for use when code reading/key coding/ reflashing of ECU'S.

I've had keys wiped and other modules wiped when the battery voltage drops below 12.5.

[Penelope Stopit]

robbocop33 said:

I didn't say i was going to flash an ecu with a car running? You want to know what vehicle's ecu im flashing with the engine running when i haven't said that's what i'm doing??Eh?
Anyway, back to reality, i'm using Renault can clip to code a spare key card in this instance. I tried hooking up my charger and at the battery it was showing 13 volts, which obviously isn't enough for this application as low voltage warning came up.
I've got a maintainer ordered now anyway.

Yes I know you didn't mention that the car would be running, you did mention about a 30 Amp radiator fan kicking in

Now bearing in mind that an engines water won't get hot and a radiator fan won't kick in unless the engine is running or has been run up to temperature, I rightly or wrongly in this case suspected that you were considering flashing an ECU while the engine was running

Have you noticed that there is no malice in my posts?

robbocop33 said:

Yes, sorry for my mind boggling stupidity, battery is brand new incidentally, i was clever enough to manage to buy one all on my own, it was quite difficult though! People have said you need a good steady supply to cope if say a 30 amp radiator fan kicks in etc while flashing an ecu in particular, i'll ignore those particulary mind boggling stupid real life testimonies though, facilitating the need for a steady voltage supply.

[Penelope Stopit]

melhookv12 said:

Just to even things out.
Jaguar actually supply a battery maintainer for use when code reading/key coding/ reflashing of ECU'S.

I've had keys wiped and other modules wiped when the battery voltage drops below 12.5.

Thank you for this, it's very interesting and also an eye opener that vehicles produced after 2010 seem to be having the problems and the notice was issued in 2012

[robbocop33]

Penelope Stopit said:

Thank you for this, it's very interesting and also an eye opener that vehicles produced after 2010 seem to be having the problems and the notice was issued in 2012

Ah, normal non condescending person,how are you?Anyway i agree there are so many anomalies that crop up from year to year on cars, and even as i found out versions of particular brand specific software can change from version to version.
The renault can clip older versions needs 13.6v+, newest version doesn't need that much? And to make it more confusing is the renault software reads lower voltage than it actually is! And i think it must take 'it' s' readings as read!
Even heard a good lot of people having the cars running to keep the voltage up when doing flashes etc on various modules with no ill effects, by instinct i would have thought that was a no-no but there's only one a way to find out i suppose.