Got in the car to go home from work, the batt light came on and warning in display not charging pull over.
I drove it home approx 40 miles, switched off engine, restated batt light and warning gone.
Checked charge rate all ok.
Loaded up electrics fan, ac hrw etc.
Engine cooling fan came on
then noticed the temp gauge and fuel gauge had shot up.
Checked engine it wasnt overheating or anywhere near that hot i would say normal after a run 80-90 degrees.
switched engine off and restarted fuel gauge on full (it was at top of red before problem) coolant temp gauge now on half engine fans on full!!
checked fault codes, no faults in engine ecu thats with a generic code reader and also a code reader that i can select specific manufacturer which allows more interigation.
checked data through the code reader engine coolant temp 130 degrees !!! fuel temp minus 10 !!!
now scratching head
turned everything off and tried a good old battery reset.
rechecked still the same.
checked all fuses - ok
checked as many earths as i could find under bonnet - ok
removed instrument panel stripped and checked circuit board - appears ok
checked as many earths as i could find behind dash, glove box A pillars - ok
tried a second hand BCM - still the same

Still unresolved-Checked wiring at transmission as this is a known issue, made no difference. I am going to open up Engine ECU an check for solder issues, and then possibly send for testing if not resolved.

I tested the crap out of this, took teh loom out to check for breaks as I seemed to have a short somewhere, with loom out I connected everything and found fault had gone, used wiggle test, and nothing. Retraced and noticed AIR con switch was disconnected still, I reconnected and fault reappeared. Who would have thought a air con switch internal short could have so many no related effects. Hope this helps someone else.
James

Peter
You should have an award for 'Efforts over and above the norm'.
James
I propose you as the first recipient of it!.

Ed Kaps