Electrical Shorting or other problem

Please help - anything, I’m not even sure what direction I’m facing at the momment.
Yesterday I drove my car out of my driveway, everything was perfect, parked it on the footpath, came back 15 mins later and when i turned the ignition to prime, the mfr clicked 20+(times really quickly while the oil, fuel pressure?(the orange light) and battery light on the dash are sort of dimming in and out. trying to crank it over makes everything cut out. turning the lights or high beams on makes everything cut out (even with just accessories on) (the parkers work but are very dim). the stereo is working fine. Fuses are fine, tested the battery it’s at 12.3v (a little low?), just put it on the charger then, it’s doing a dusulphatation cycle.

The only thing out of the ordianary was that I checked the oil and the filled the windscreen washer bottle before i drove it out the driveway.

After it died, I pulled the head unit out of it, because I put it in myself and didn’t run a new power cable from it from the battery for it, I wouldn’t have been surprised if this is the cause of my short, but nothing I can see looks astray (no melted wires, and as i said the stereo is one of the few things that is working).
Oh when i turn the lights on something behind the middle a/c vents clicks on and off. windscreen wipers work really slowly or not at all on the faster speeds.

Should I take it to honda service (maybe something like the intergrated control unit is playing up?) or get an auto sparky to look at it? my regular mech is sick till monday.

Throw any ideas you have at me, I’m keen for anything, I love my teg but this is stretching the friendship.

First thing to do is check you batt. cables, remove the clamps, clean both the cable clamps and the batt. posts, check and make sure your main fuses, in under hood fise box are screwed in tight, along with the batt. and alt. cables in the fuse box.
You should also check your chassis ground, [under batt. box] and motor ground.
All the above should be removed cleaned and reconnected.:stuck_out_tongue: 94

did the above and replaced the battery, and all is better. Thanks