Battery test (In automotive diagnostic )

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Re: Battery test (In automotive diagnostic )

Post by FioranoCars » Tue Aug 22, 2017 9:24 am

Thanks Steve, a great and detailed overview of the battery test.

A couple of things :D ... first from your example

Would for a 3.3amp output from the alternator, not render 373mv of ripple as a fail, or at least and bright shade of yellow?
Second, from the initial voltage and output of alternator (and load between) could a traffic light be added to current output? (In this example with a 12.5v starting voltage, clearly alternator is not needing output much, but other times a simple formula(yes, with compromises!) might via colour highlight a suspect issue.
Providing a zoom into the waveform for advanced user interpretation
Icing time, for the ripple, allow us to see the A/C capture you took (assuming you do switch the scope to A/C mode from DC during the test?

You did not for your example use an extended test, and that's where I have a few extra issues, or requests :idea: and I'm sure I've written more detailed requests, but from memory, here are the highlights ...
1. Traffic lights for client visibility - they like colour! The extended have no traffic lights at the mo
2. More the extended results to be with the Starter not at end
3. add option for alternator extended (and show results under that heading if selected)
4. Show peak figures, but also the mid cranking averages, as that's where the actual VD is more qualifyable as being good or bad, so rather than at 500+amps, the figures from typically 150-250 amps of the post initial inertia inrush ? Both are valid for different reasons, so putting both on the report (2 columns - Peak and "normalised") the resistance figures need only 1 set, but voltage at starter, amps, and pos/neg volt drops need 2 sets please (IMHO) :!:
5. From memory I think the starter resistance remains the same on the standard and exteneded tests, which is wrong, as the cable/ground paths can be removed. on the standard test, maybe stating "Starter and wiring" or avoid confusion?

Anyway, thanks for the explanation, and look forward to hearing if these and some of the historic feature requests might make a future edition of the PicoDiagnostics software.


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Re: Battery test (In automotive diagnostic )

Post by STC » Tue Aug 22, 2017 9:40 pm

I'm not getting this, it's over complication.

I know the battery in my Van is duff and I need a new one. Have had to jump it with a boost pack every morning for the last 10 days or so.

Saturday evening I took the Negative Lead of the battery and substituted my Jump pack for the Battery. Sunday morning it burst into life, Monday Morning I could have driven it to the corner shop in first gear on the starter with no fuel whilst scoping 4 things of your choice.

Charging - tick
Parasitic Drain -tick
Jump Box - tick
Battery - KICK

It needs a new battery and my Jump pack is tip top - Two Birds One Stone - Happy Days!!

A simple belt and braces accurate, guaranteed diagnosis !! Any Viable written challenge welcome !

Simple ???

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