Model Railway Forum

If the battery on a car goes completely flat and you charge it why doesn’t the computer need reprogramming?

yelrow wrote: ↑Tue Jan 14, 2020 5:22 pm when i had my disco, had similar worry about computer, so, used battery from heathers car, with jump leads, purely to keep, electrics, undisturbed. Changed big, disco battery, then unclipped jump leads, and status quo, as before. No interuption, in computer, clock, or owt. Just a thought. john

Quite correct John, done it 1000s of times. I would not take a wheelbarrow to Halfords.

Under normal circumstances neither would I. But the own brand one they sell is £110 rather than £300 for the named brands and has a 5 year guarantee over a 3 year one for the 'names'.
That's a big difference and worth fighting for.

And it's raining so I didn't fancy grubbing around under the bonnet in this weather.

Halfords prices can be beaten easily Steve, just do a bit more research.

WTD, its not the going flat that bothers the computer, its disconnecting the battery that causes the reprog. There is a circuit with flat battery still in situ. Only found this out with my first disco.

What keeps the computer going when the battery is flat

Walkingthedog wrote: ↑Tue Jan 14, 2020 8:37 pm What keeps the computer going when the battery is flat

Witchcraft.

WTD, its never totally flat, in my experience.. Never had an occasion, where the clock actually stopped. The computer and clock, draw very little. Remember with disco, there was not enough to crank motor, but they still worked. Its the breaking of the circuit that needs avoiding, but, thats what was explained to me, by Land Rover.

Yes makes sense. You idea using jump leads was very clever.

brian1951 wrote: ↑Tue Jan 14, 2020 7:19 pm Halfords prices can be beaten easily Steve, just do a bit more research.

I’m struggling to match their price and that five year guarantee unless I look at a completely unknown brand and seller.

But I have found a couple of how to videos on YouTube which, if they can be believed, don’t require any special tools - a rummage under the bonnet tomorrow may be beneficial.

If I can get the thing out, or at least see how to do it, I may end up stripping it in their car park and doing a deal with Halfords for their techie to use his machine. It all hinges on being able to release the airbox without making a complete horlicks of the whole thing.