Intermittent Charging Fault, message + battery light

Datatek said:

The 12.96 is the surface charge, look at it after 1 hour. S5 95A sounds like an AGM battery which may not be suitable for your car. AGM batteries require a different charging regime to normal batteries. Bosch these days is just a brand name, likely to be made in the same eastern European countries and factories as Varta and other brands as far as I can see.
I can't answer you other points as I am not familiar with you model.

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Latest. Bought new battery. Identical to the Bosche battery already on the car. As I don't have means to tell car it's got a new battery, took it to local specialist. They changed battery. As I drove away "ping" gearbox fault! (that's a new one!) Ping, restricted performance! (also new ) Back to garage. "nothing to do with us mate!! “
Drive home. After turning engine off would run normally for differing intervals before warnings started pinging. 2 or 3 starts later, including booting it in" sport" () got home.
So, if it's not battery, must be alternator. Fitted new alternator and drive belt. Test drive - NO FAULTS!
Went on holiday. 400 miles of trouble free motoring.
Yesterday, returning from friends house 15 miles away "ping" stability control fault, abs fault, etc etc. This was after 3 miles. Turned engine off, restarted, no faults. Drove home, no more faults.
I am now thinking it is damaged BMS wire plugged into negative battery terminal.
If this wire is making/breaking intermittently, would that throw the failure warnings?
I am thinking if, when it breaks, it is telling the ECU there is no battery voltage, the ECU starts throwing codes. Is that a possibility? Any thoughts? (aren't intermittent faults great! )

ok so you put a new battery on, then a new alternator.

now, you need to fully charge the battery with a battery charger and try again. the smart alternator will eventually learn your new battery profile

kermit_rr said:

ok so you put a new battery on, then a new alternator.

now, you need to fully charge the battery with a battery charger and try again. the smart alternator will eventually learn your new battery profile

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I have it connected to a Ctec battery charger which says fully charged. But would a low charge explain the intermittent nature if the faults?
Following further investigation on this site, I have discovered there is no drain tube under the fascia below the windscreen, so water gas been running onto the negative battery terminal for some considerable time. Should the unit incorporated in the negative battery terminal be suffering from water ingress and would that explain the faults?