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Old 09-19-2011, 11:28 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
Good news! (audible sigh of relief!)

The seemingly complex & comprehensive cluster death (amazingly) was solved today (simply) by replacing the (bad) BMW battery!
- Pictorial discussion of charging, testing, removing, & replacing the BMW E39 battery

Here is a pic, taken today, as I breezed along highway 85 in San Jose. The tach & fuel gauge & alphanumerics were all suddenly back in operation!

Even the MID time display returned!


So the question becomes, WHY/HOW could a battery that suddenly (and without warning) "went bad" cause 'just' the following units to suddenly stop working completely?

- The tachometer was totally dead (speedo was fine)
- There were absolutely no alphanumerics on the cluster (and most indicator lights were also dead)
- The MID time alphanumerics were totally gone (but other alphanumerics were fine)
- The blue high beam indicator went inoperative (but turn indicators were fine)
- The gas gauge was inoperative most of the time (except for a brief interval in the middle, when it suddenly worked until I shut down the vehicle)
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