xantia HDi 2.0 electrical issues!?

Xantia HDi 2.0 - a real bitsa! The positive battery terminal has been replaced, everything works except the aircon supply... does its own thing and runs sometimes. Have not noticed the fans running under the bonnet...
Could live without aircon, but not starter motor. Got back from MOT - pass!!! - and started to look for aircon fault. On replacing battery - no starter! Jumping direct by wire to solenoid, starter fine, but will not fire.
I cannot find wiring diagrams for this car, can anyone help?