If you've UNLOCKED your instrument cluster...you can monitor the output of your alternator/charging system when the engine is running if you open TEST 9. When the engine is NOT running and the ignition is in position 1 or 2...then it will reveal the battery's voltage.

A alternator in good working condition should be putting out 12.8volt to around 13.8 volts. If it is spiking consistently above 14 volts (that's too high). Have you checked your belts? A slipping belt or a belt that is cracked and about to split/rip...could also have caused your momentary red battery light...as well as one of the pulleys/belt tensioners.

Here's the instructions on how to UNLOCK the OBC (instrument cluster) so you can access the 21 TESTs that are available:

Click this link for a description of all 21 TESTs: http://www.cardomain.com/ride/313409...series/page-6/

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Q {BMW CCA Member #191509}
2006 E53 X5 4.4i (Sterling Gray) 12/05 mfg date <<~>> 97 740iL (Arctic Silver) 3/97 mfg date
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