E38 Monitor/LCD Display Problems

An E38 1997. The moniotr likes to flicker on and off, and will also shut off for long periods of time. The monitor sometimes flickers off coniciding with a push of the accelerator(most times, when it is not fully off). When the moitor is sometimes on it is faint(as in the brightness looks like it is turned right down) and a slight tap around the monitor surrounds, makes the moniotr flicker. Also the phone likes to turn on whenever it feels like as well. These two problems might be connected i don't know. Could it be that the battery is not up to capacity? (cause the battery light did come up once the other day, but then disappeared). Can anyone help please, Thanks

Thomas.

I'd definitely check the battery - it sounds like the car is running off the alternator when the engine is running and there's very little "buffer" left in the battery to abosorb surges in demand...

if it helps, my OEM BMW battery - the largest 750 size - died overnight last month. One cell was toast (wouldn't charge, boiled on starting load) and that was the whole battery gone... behaviour was similar, except it couln't turn over the engine - everything else went, and after jumpstarting the instruments brightness would surge with engine revs, too. New battery, now no problems.

HTH

Max