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Old 12-02-2010, 04:32 PM
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bluebee bluebee is offline
Seek to understand,^Value
Location: San Jose, California
Join Date: Mar 2008
Posts: 25,236
Mein Auto: 02 BMW 525i M54 auto 130K
Do YOU have an idea about what this chamber is for and how it might work?
I realize I'm asking questions that have never been asked before, so perhaps that's why nobody has stepped forward with an answer as to what that separate floating black box does in the expansion tank, in practice.

Also, nobody has outlined what that failure mode could be indicating, now that my floating box was pinned stuck by the post.

Even with those unanswered enigmas, here's another challenge for our combined tribal knowledge of the cooling system.

How do you think this electrical level sensor works anyway? Of course, the magnetic disc, when it surrounds the tip of the electrical level sensor, somehow triggers the low coolant warning; but how does it actually work?

Here's a closeup. I wonder what's in that tiny bulb on the stalk of the electrical level sensor.

I don't know how this triggers the low coolant light. Do you?
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