12.5 volts is a bit over 50% charged but the battery may not be able to provide enough current. Check the earth strap from engine to chassis and the wire from battery to starter for corrosion inside the plastic. Th Varta Battery on mine was like that, particularly in cold weather, plenty of volts but no power.
Back to work? Bloody hot here at the moment. Hope you had a good break.Have the battery load tested. It may hold enough stored power for a first Stat up and then fade quite quickly. This normally means the battery is tired. A load and capacity test will confirm this
It was great thanks young man. We did notice in spain it was truly hot through the day but would cool down nicely when it was the evening but here at home it's still stays warm. We are glad to be back and sleeping in my own bed was real bliss
had exactly the same with a BMW years ago, started fine from cold that morning but later in the day wouldn't even turn the engine over.
Age of the battery is immaterial. It really sounds like a bad earth or connection. Check the earth strap from engine to chassis and the wire from battery to starter for corrosion inside the plastic. Also check the fuse box for a smell of burning. If you have some jump leads, connect one from the engine block to the battery negative to rule out the earth strap.
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