"Larry Jaques" wrote in message
...
On Thu, 12 Dec 2013 09:08:03 -0500, "Jim Wilkins"
wrote:

The error codes didn't pin down the problem very
closely.

So, engineers have finally figured a way to put the "shotgunning"
into
code for electronic troubleshooting, did they? It must have been
those pesky used-car engineers, huh?

In 1970 I went into an Army course on repairing -very- complex
electronics. They told us that there was a troubleshooting procedure
but they had found that having repairmen memorize how the circuits
work (in excruciating detail) was more effective, plus we wouldn't
have to carry around and risk losing the manuals which were
classified.

At that time the draft gave them a large enough pool of engineering
grads to make it practical. After the draft ended they had to revert
to board-swapping. The 40-week course gave them four graduates out of
almost 100 starters. The others were allowed to enter less demanding
courses.
http://schroeder-family.us/military.htm

After I got out I went into the custom test equipment industry,
specifically for the first generation of automotive engine control
electronics and antilock brakes, and found out how hard it is to
identify faults without adding excessive monitoring circuitry which
has an equal chance of failing. You can detect a lot of problems
easily by measuring the power supply current, for example, but an
out-of-spec value doesn't tell you what caused it.


When I bought the shop manuals for it ...

But you saved a lot of money buying it, right? wink

I figure the depreciation cost on a newer vehicle would be $1000 -
$2000 a year, so I'm ahead if I spend less than that per year on an
old one. Most years nothing breaks.
jsw