My focus has been going into Battery Saver Mode for 2 months now, had kwik fit do a check and they said the battery needs replacing even though it was brand new and fully charged. Everything else works fine apart from the radio, Start/Stop and USB Slots. BMS issue maybe??? Anyone else had this problem.

Edited February 8, 20206 yr by Phil Toll
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Have you tried resetting the bms?

Check the battery voltage across the terminals, it should be around 12.5v or more without the engine running. And over 13.8v with the engine running.

If the battery is bad you will notice problems at startup. It might take a few seconds longer to start the engine. A good battery should start the engine straight away.

It could be too many short trips does not charge the battery enough. You could connect a solar battery charger across the battery and leave it inside the car near the window. 

Should be simple enough for someone competent to do a proper battery test to make sure theres not a problem maybe with just one cell. ( did kwikfit do that ?) . So maybe just a dud battery it does happen.

Its been happening constantly since December, had it in kwilfit on Wednesday they said the battery had a dead cell, replaced the battery with a brand new one and charged it over night and then resetted the BMS before taking it back to kwik fit (went into battery saver mode on the way), they said the new battery also had a dead cell, then i got them to check the previous battery which they said needed replacing  and the test came out as good battery cully charged.

I have been monitoring the voltage and its not dropped at all, remained at a constant level (over 12.5 engine off and over 13.8 when running).

Everything else on the car works just fine, starts perfectly every time. 

When the bms comes on what was running on the car. Heater, windscreen heaters, radio, lights, etc. Might be worth checking the earthing bolts are tight. Could be a loose electrical connection. If it starts ok and the battery is good, it must be getting a false reading somewhere. You could try using it and not turning on one device at a time to see if the problem goes away. I.e don't  use the heater blower for one journey, then lights ...