Just driven back in the biblical rain. 2 hours. As I’m nearing home, the heater blew faster then dropped back down, and the battery warning light came on and stayed on.

Running the ignition/reset test I get 969e on the dash.

Whats the problem?

Dont know about the code but the symptoms with the fan may indicate alternator / regulator failed.

no idea about the error code but the fault suggests either:

1. aux drive belt has snapped

2. battery has failed internally

3. alternator has packed in

4. charge circuit has packed in

5. wire come off/water got in somewhere

How old is the battery? If its Ford could be original…
Which is old/bad possibly
Disconnect..leave an hour then reconnect.

battery looks old

If its no date, it could be original…

Easy check if you have a multimeter is to check the voltage with the engine running at more than an idle. Should be around 14.5v. If its much lower or higher than that then it’ll give a good indication of where the problem is.

driving it, the light goes off every so often. then comes on again

possibly a bad connection somewhere to the alternator or battery.

Might not be the cause but there is a known fault with Focus dashboards.

The dash on my 03 starting doing all sorts of weird things like rev clock raising and falling with no change in engine speed and warning lights coming on an off for no reason.

Ford never did a recall but IIRC a replacement was about £70 (£100 fitted).