Hi.
i need help with a 2003 boxster s. the car suddenly started cutting out after a battery change a feeks ago, it made it 250 miles before it started playing up. i have checked it for trouble codes and nothing found, i have changed the dme and the starter relays, checked 9 earth points, been through as much wiring as possible and found nothing, checked the alarm module for water ingress and no faults there.
The car will now start and sometimes tickover and run perfectly for maybe a minuite, an hour or half a day then it just stops and wont turn over or power the engine circuite up at all.
ive checked the ignition switch again with no faults.
im really sure its suddenly loosing a power supply but where does the cars interior electrics powered from?
Ive traced the one and only one main battery lead through the bulk head, under the centre console and through the rear fire wall where it connects the the starter motor lead, but cant find any where were a junction or tee off is to power the fuse box, ignition ect.
has anyone any ideas?
the lights, radio and all other auxilleries stay powered up.
Help me pweeese.

(((