E32 loosing charge

[Loke]

First,

Pardon for abusing the E34 forum with a E32 problem, but I highly doubt its a E32 specific problem - and the E32 forum had like um 4 posts so...

Well, my dads E32 started getting "Water flow low" message on his computer. After water level check, and no abnormal temp readings - we found out that the battery was so poor it could barely drive the OBC let alone the radio. So I recon the car OBC went a little nuts due to power shortage.

So my conclusion so far is either the battery needs replacement, or the charging system have problems. The battery voltage reads 11.3V and the charging voltage from the dynamo (eng word?) is 14.3V. AFAIK 11.3V for the battery is low, but 14.3V from the dynamo is about what it should be.

No fuses are blown. I dont know how else I can meassure to see if the charging system is faulty. The battery fluid is at correct level. Can it be something else than the battery?

Also, we bought a new battery today and the battery dealer told us his books said a 730iA 6-reihe was outfitted with a 75mAh battery. However, when we came home the already fitted battery was 85mAh and WAY bigger than the replacement battery.

[Unregistered]

75mAh battery

Thats 75Ah I recon, not mAh.

[George M]

since you have a new battery then you need to monitor how well it charges. Perform OBC test no. 9...check archives for details to ascertain operating voltage. If alternator is charging properly, voltage should be ~14 or so...mine reads just under that and charges the battery fine...somewhat dependent on voltage regulator output.
With the engine off, static voltage at the charging post terminal should read ~12.2 volts or so if your battery is accepting a good charge.
HTH,
George
also with E-32...yes you can get false OBC and CCM readouts if your operating voltage is too low.