Bear with me. I know it's about a Prius, but that's not relevant.
This is the story of how to really track down a fault, in this case a failed display screen. It's not a slick site, but it's a good read.
The Toyota answer to these issues is to swap the unit, but for this guy, that just wasn't good enough...
techno-fandom.org/~hobbit/cars/mfd/index.html
|
|
Wow. The world would be a much better place if there were more people like that guy!
|
A total mystery to me........Much admired, though.
I bet he'd have a job fixing one of the firm's Priuses. Destroyed over the weekend when 2 tons of scaffolding fell on it somewhere in Yorkshire
Haven't got all the details but if a photo turns up, I'll post it.
Ted
|
>>2 tons of scaffolding fell on it
Probably got a flat battery.
|
Absolute respect to that guy.
I've seen this in my industry too. The 'engineers' (I know there is widespread concern about this word being used in this context) who used to repair the big production laser printers (think up to 30ft long and 1.5 tonnes in total weight) we were involved with would often go to component level to trace and repair faults. One guy that I am thinking of in particular knew what voltages and waveforms to expect at various points on various wires and boards in the models he dealt with, and would actually remove, repair, and refit boards or components on site. Consistently achieved the highest first time fix rate, lowest recall rate, lowest used parts cost, and highest customer satisfaction rates in the business by some margin, if this did come at the expense of call rate per day. Thankfully the management were intelligent enough to realise the efficiency of his way of working.
Nowadays, the same equivalent people will simply replace an entire assembly. Apart from cost, this is also often done in vain, as like car engine management systems, the fault symptoms in these devices often manifest themselves in an entirely different area or system to the one containing the actual fault.
People with this skill and tenacity are increasingly rare. It's a shame.
Last edited by: DP on Tue 26 Jun 12 at 12:00
|
Good article, a very interesting read.
I fixed a clock in a Rover 214 some years ago, where I was going to replace it, but the new part price was firmly in the "you're having a laugh" category.
Similar to the Prius controller, the cause of the failure on mine was several soldered joints but a lot more obviously at fault. In the Rover's case though, it was more "how the heck did this work in the first place" as the soldering was so bad.
|
I moved into an office whose A/C only worked intermittently. After we'd made several fault reports that didn't resolve the issue, I started removing covers I shouldn't, I found the 'engineers' log that showed this was a long term problem that had never been resolved.
I finally found the chocolate strip connectors on the end of each PCB had every screw loose that should've been holding the wires. I guess it had been like this since the day it was installed.
Result, working A/C until the day I retired.
|
Long time ago when I was programming, we had a real time computer system which kept crashing - intermittently. No one could explain it : the engineers blamed the system,, the programmers blamed the hardware (parts of which were new).
I eventually decided that there was a complex interaction between the two sets of new hardware: a tape drive and a communications mutliplexer and set up a test program which looped writing to the tape deck and issued a message on one channel and receiving it on the other. Lo and behold, I got consistent faults which explained why the system crashed. The company's Chief Engineer - an electronics engineer - refused to believe it and I was forced to demonstrate the fault to him personally. (on a Monday after I had worked all weekend)
As he had written several memos emphatically blaming the software , he was not best pleased to be forced to eat humble pie.
Unsurprisingly the company eventually went bust. . (Anyone remember Ferranti?)
Last edited by: madf on Tue 26 Jun 12 at 19:04
|
Thats the way to fix it,
I used to do something similar to Volvo MFD units.
two problems, as a repairer , one is customers Dont appreciate the effort &
2nd if the unit fails when they are on holiday abroad they come back and sue you ! for loss of holiday and damages ! been there done that !
So these days its simple to replace and if it fails you sue the company that supplies it !
End OF
|
One for the dedicated technicians - oilburner
