Hello. I have found the fault code listing and it is exactly as you described. No service bulletins relate to this fault code. This fault sounds like it would only be a camshaft sensor internal fault as this is the most common problem. If you use a BMW dealership they will be able to see a lot more information and run a specific test plan provided by BMW to determine if the sensor is good or bad and if further diag. will be needed. Most likely this will only be a sensor replacement. The sensor is pretty accessable, most dealers would charge an initial 1 hour diag and about .75-1 hour for replacement. If you would like I can find the general price of the part tomorrow at work for you but I will need the last seven of the Vin to check this. Most likely this will be pretty straight forward repair, if it proves to be more than the sensor like wiring, internal control module failure, or mechanical at the pickup on the cam could be possible but unlikely. Most of the time it is cut and dry with this fault. I hope this is helpful. Let me know if you need any more information I can try to help you with.Thank you.
P1525 10165 'A' Camshaft Position Actuator Control Open Circuit (Bank 1)
BMW Mechanic
Level 1 BMW Master Certification, 9 Years Dealer experience, Team Leader, Shop Foreman