On Tue, 15 Mar 2016 19:59:53 -0500, legg wrote:

On Tue, 15 Mar 2016 20:01:54 -0000 (UTC), Cursitor Doom
wrote:

On Tue, 15 Mar 2016 14:25:41 -0500, legg wrote:

On Tue, 15 Mar 2016 14:04:46 -0000 (UTC), Cursitor Doom
wrote:

On Tue, 15 Mar 2016 09:58:03 -0500, legg wrote:

On Tue, 15 Mar 2016 11:05:24 -0000 (UTC), Cursitor Doom
wrote:

But this is really about trying to rescue the old one. They don't
come cheap!

The issue is with the new part, not the old one.

Wrong! The question *solely* concerns the *old* unit that failed.

The issue is your dissatisfaction with the repaired automobile.

You're not in a position to resurrect the old ECU.

The new ECU in all probability just requires a software tweak. My
question was about the OLD one (at the risk of repeating myself).

There's not much you can tell from a photograph of limited resolution.
Looking at what you've offered, you might re-examine locally:

http://www.magma.ca/~legg/TVS/EMU_captive_detritus.jpg
http://www.magma.ca/~legg/TVS/EMU_green_reflection.jpg
http://www.magma.ca/~legg/TVS/EMU_red_reflection.jpg
http://www.magma.ca/~legg/TVS/EMU_so...ontaminant.jpg
http://www.magma.ca/~legg/TVS/EMU_so...taminant_2.jpg

I expect these are mostly reflections in the protective epoxy, or
flow/tension marks formed in its application, but could be signs of
contamination or damage.

Even checking point to point contact is a trial with this stuff.

Vibration produces intermittent faults on assemblies (where the parts
don't actually shear off completely) The most suspect parts are those
with mechanical attributes - the crystal as previously suggested, the
connectors and bulky components. Reflowing the SJ of the latter might be
informative - any uncharacteristic loosness in the soldered material of
the melted joint is a giveaway.

As previous - an intermittent fault is unlikely to result in repeated
DOA symptoms, but it can be recorded for posterity in the firmware, with
DOA symptoms, or break small-signal paths with the same effect.

Did you try a reset on the 'dead' unit, before replacing it?

The fact that its replacement didn't involve the surrender of the defect
unit (for a discount in pricing) is a signal from the mfr regarding
their view on the viability of repair. They are in the most sensible
position to do so, after-warranty.

RL

Many thanks for that lot above (and the other tips & suggestions others
have come up with). I don't think I will have sufficient time at this
stage to see this through to the end if it turns out to be tricky; I
can't face the prospect of this becoming another saga like the Philips
scope turned out to be.
I'll try to get the back off tomorrow...