Ok, got home from work at a reasonable time tonight. Thought I'd try and figure out the "beeping" on lock issue.
Thoughts were - Its a sensor thats being triggered due to a faulty connection/diode. Or the wiring is faulty under the dash.
Started pulling the car apart for the diodes Tas hid. Found one on the input zone wire that according to my multimeter was faulty.
This little bastard however, is tucked up under all the wires and ****
under the steering column and Tas must have been a ninja in a past life...
Damn it was a prick to get to.
So, thinking that would be the ideal one to fault, I made this little baby to replace it:
I was thinking, if it ever fails again - it'll be 100% easier to replace.
(yes the red heat shrink is so I can tell the polarity)
After installing it, and paying close attention to polarity - its not the culprit FML.
Found another diode in the boot, multimeter says faulty (now I'm just cluing on that because its still connected in the circuit - its going to have minimal voltage on either side) - replace said diode....
Its not, car still beeps when locking.
Cracked the shits, went inside - started making dinner.