Tacho and SI lights...Lithium SI Batts?

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soul4t
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Posts: 381
Joined: Wed Feb 23, 2011 11:00 pm
Location: Bristol

Post Tue Mar 19, 2013 10:07 pm

Hi All!

I did quite a bit of research and assumed that my SI batteries needed replacing.

Symptoms:

Tacho didn't budge on first start in cold weather, problem has been slowly getting more frequent.

Couldn't reset SI lights easilly...only using wire bridging method at diag port.

Recently reset lights and within 2 days yellow and red lights were back on and 'Inspection' light illumined...'Oil Service' is not illumined...yet!

So I bought the batteries and dismantled the instrument cluster, soldering iron at the ready...nervously, then I found that it has the lithium batteries! The original Sanyo ones:

Image

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Do people think that the batteries are likely to be the problem? I stupidly didn't check the voltage...don't ask...either way, The batteries look a bit of a challenge to desolder and resolder on.

Is it easy enough you guys think?

Cheers!
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Brianmoooore
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Joined: Mon Jan 10, 2005 11:00 pm

Post Tue Mar 19, 2013 10:13 pm

Whether changing the batteries is " a bit of a challenge", depends on your skill levels with a soldering iron. It's an easy job as soldering jobs go (try a 64 pin modern surface mount IC without the correct equipment!), but there's a limit to how much heat the board will stand.
Batteries must be 3 volt (not 3.6V) lithum, non rechargeable.
Put a meter across your existing batteries and see what voltage they are producing.