More About Points »
Maybe a power surge? Start by Checking all fuse w/ proper circuit tester, step on w/ owners manual
Need more info. Exact wording of "error message" would be helpful. Such as "steering assist inactive" maybe you might have a stored diagnostic fault # is so what is fault?
Have you inspected for Blown fuse? Poor connection/corrosion? No input signal seen from fan command switch?
Possible trans fluid low? Any warning lamps on? If so what diagnostics fault # are present?
Trans. fluid level check? I would speculate that your transmission might be crying for help/service. Some of the XC90 suffer from premature failure partly because of some drive axle cross contamination w/ ATF. I would suggest to take it to some that has a factory level diagnostics tool. To rule out a possible electrical malfunction and maybe they look over the vehicle before it becomes inop.
Agreed, if coolant level is correct. Would seem to be an electrical malfunction.
If the cat is not defective or one last test could be to confirm is no false/unmetered air within the exhaust system. Best bet to have a qualified service center perform a smoke leak test while vehicle exhaust system cold. Good luck.
Do NOT drive! Need to know how vehicle started to manifest its symptom. Was Temperature Gauge running hot recently prior to smoke? Because i still think if not related to temperature "a possible silver lining" could be Breather system, when restricted could cause blue smoke(crankcase could have too much psi) Hence the oil consumption ie smoke from tailpipe. Agree with other suggestion to have it check out. I would search for a quality Bmw independent near you bimrs(.)org Could help locate a good BMW repair facility. Good luck.