rat flan

[spuffock]

I have been looking for info on the repair of laptops , and all I find is detailed instructions on how to dismantle one.
I am reminded of a Monty Python recipe for rat flan, which went into great detail about the lengthy and thoroughly inhumane manner in which the rat was to be killed, and concluded "then make a flan of it."
Any comments?

 

[Nigel Goodwin]

Repair is likely to be down to module replacement (just like a desktop PC), except that modules are likely to be VERY expensive, and probably not available.

 

[spuffock]

But its probably only a simple fault. The 15v gets as far as a FET, which doesnt switch on. This is driven by a transistor, which doesnt switch on. The base of this goes down a via to somewhere.
By connecting a lab power supply across the battery, I can get the thing to run, but it stops without the battery. Leaving the psu there is fraught, I cant quite come to terms with the idea of imminent explosion.
It seems a shame to chuck it in the skip, the spec is a LOT better than the workshop computer.

 

[Nigel Goodwin]

You need a service manual then (or at least a circuit diagram), assuming they are even available?.

BTW, are you sure the battery isn't faulty?, they are often stuffed full of electronics, and a fault in there might prevent the computer working at all.

 

[spuffock]

It'll work off the battery for a while, but it wont charge it. I'm a bit leery of going in with a sledgehammer to charge the battery externally, since the microcontroller inside may well deduce what I'm up to and disable the pack permanently.
If I could find out what all the pins on the battery connector do, I might be able to fool the laptop into believing that the lashup and lead-acid is really a pukka battery pack, then I'd have something useful.

 

[justDIY]

I've got a similar laptop - works great off battery, but not at all off DC input - and won't charge the battery.

my solutions is to run it off two batteries for about 6 hours, then recharge the batteries in an older laptop (gets old after the first few times). one of these days I'll see if I can hotwire 15v straight into the battery power connector, without a battery - my guess is it won't work, thanks to smart-battery protection like you've pointed out.