Hi I have this fault on my 2004 L322 "0xB battery Diconnect unit 1" I thought I had cleared it using my GAP IID Tool but it came back on my way home from work also the traction control light flashed on at the same time.
Could this be a battery fault or is more than likely to be the ECU that needs changing.
I also have heavy power steering this happen a few days ago I'm thinking the faults might be related any ideas are welcome.

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I have just taken a battery reading from the IID tool and it reading 11.7 volts so I will try to change the battery is there anything i need to be aware of if i disconnect the battery for more than a day.