Circuit Boards

Better built and better specced. Early car electronics were dire.

It'll be simply that the car ones are built better. It costs a bit more to do so, but a) they have to be because of the expected life and conditions they're operated on, b) on something which costs 10K there's more money available, and c) a manufacturer which skimped would soon get a terrible reputation - people complain a lot more about their cars not working than their washing machines.

Well washing machines pcbs get shaken a lot don't they, they also seem to suffer issues of solder joints going dry on mains carrying parts. My suspicion is they are not made very well in the first place with lead free solder that is mostly crap. In cars, much of the kit is better made and housed at least the sensitive stuff is as its a higher value product and people would expect it not to go wrong for both safety reasons and of course reliability. Washing machines seem to have an accepted official life of no more than 7 years or so these days, though many do last longer of course. Brian

Cheapest components? Car electronics are in a hostile environment and are expected to have a decent life. Components specified for the odd voltage spike you get in cars, rather than the absolute minimum in a more controlled environment.

So saying, the PCB in my Viessmann boiler is beautifully made. As well it might be at a spare part price of 500 quid. ;-)

Well for some value of "incredibly". According to the AA etc over half of all breakdown calls they get are caused by electrical faults.

In both cases, of course, the manufacturers want the device to fail after a few years, ideally after the guarantee has expired so you buy a new one. Sometimes they get their timing wrong, of course.

and, of course, for the very large temperature swing

Failing computer boards cost me ?2000 in repairs on my last car (Citroen). I've gone for a car made in a different country now, in the hope that the boards won't be made in the same factory.

Clive Page wrote in news: snipped-for-privacy@mid.individual.net:

Maybe - but rarely due to the "brains" of the car.

Input or output devices could cause the board to fail!

Could well be. The same could be said of a washing machine or boiler. But is it down to a circuit board?

Do Citroen use their own?

Never ceases to amaze me - the cost of some of those spares. No way can it cost much more than a laptop.

I thought batteries were the prime cause these days.

NT

That is an electrical fault ;-)

Or was that your point?

Crucial (near) breakdowns I have had in the last few years have been fuel pumps.

It pays to consult the reliability figures published by insurance companies and others. There are some exceptions but the general pattern is clear: Japanese cars made in Japan are most reliable, Japanese brands made in European factories are next, and European brands made in Europe are least reliable. One can draw one's own conclusions about the relative contributions of good design and good workmanship.

yeees

the point was it's mainly batteries not ECUs.

NT

Of course, but the board should be designed to be immune. Also in my case two boards were involved. When one faulty board was replaced by the latest version, it could not communicate with the other board, so that had to be replaced by the latest version as well.

The car battery? Quite likely. Quiescent draw in some cars means it may not last leaving the car when on holiday (a long one). And no battery lasts for ever.

Probably just me, but I didn't immediately think of a flat battery as a fault as a such. Or a puncture as a breakdown, etc. Neither would I call out a breakdown service for.

The white goods market is very competitive, and all that counts is price. Therefore the manufacturer cuts costs wherever possible - a quarter of a penny on a part is a worthwhile saving. That means the boundaries of reliability are pushed in the name of price, so there's no margin to spare if anything goes wrong.

Theo

Big snag with all that is you're in the hands of the garage. And have to accept what they say. Not the most honest trade in the world - or the most competent.

There used to be a contributor to here who re-conned car ECUs on an exchange basis (ATP?). Rather like Geoff at CET?.

He said that something like 60% of the 'faulty' boards he got back after an exchange was was supplied were no fault found. But the customer still got charged.