loosing charge advice needed

Hi i posted up about my c3 2002 loosing charge a while ago and still got the issue.

Background The car runs fine but when its sat engine off there is an intermittent first turn over none start basically goes to turn over, dash lights go off but second attempt it starts OK. The clock resets etc etc.

I have had the alternator checked and that was confirmed as good. I have changed the battery which is a proven good battery but the issue is still there. This has resulted in the power steering playing up after a hard break so is a cause for concern.

What I have noticed is that the temp gauge tends to rise when sat in traffic but no overheating however as i drive it still rises up to the red? But turn the engine off leave for 5 minutes and all's back to normal. I am thinking the fan isn't kicking in but not 100% as not had time to leave it running to check it so when i get a moment I will check this and if needed do a 12v check to fan directly to ensure the fan is working.

Now here's the strange thing. I was sat waiting to pick the wife up from work I was early so was sat engine off key on with radio running all of a sudden I hear a beeping I look down to see the battery light flashing and the temp gauge showing in the red although the engine wasn't running why would this be???

I shut the car down fully then to on the battery light was ok but still showed high temp turn off and after about 5 minutes the temp gauge was clear.

surly if the engine is not running then these lights should not have illuminated and a radio don't use that much power that it drains a good battery so could I have a issue with the fan relay shorting to ground? If the relay is shorting then this may account for this strange behavior?

Where is the relay to the fan. where's the fuse to check that to

Any ideas on what could be causing what seems to be a parasitic draw or causing this issue??

Thanks guys

I had a similar starting issue where there was excessively voltage drop when starting. This caused dash and clock to reset, probably other systems too but car started ok. Until one day I went to start and car was completely dead, no electrics at all, turned out to be earth wire. It runs from battery to underneath battery box, and it my case had corroded to the point it was completely severed. Not sure on your other issues but could be related to voyage drop upsetting ecu or bsi.