Ok, we have sorted out the problems tonight (well, Dave did it all actually). We traced the 4WD dash light being on down to the single pin attesa bleed connector wire under the dash. It was plugged in, so the 4WD dash light was on, hence no FWD engagement. Error code 8 is simply due to the ABS unit being unplugged and had nothing to do with the 4WD light being on.
Thanks Dave
Charlie.