X5 Questions

[chrisong]

I have a 2001 X5 4.4i that has been having sensor problems. The On Board Computer would always show "Check Coolant Lvl" and "Check Oil Lvl." After bringing it to the dealership a few times and not having it fixed, they fixed it on the third try. But my skepticism with this dealership is quite high. My question is how can I check if the dealership merely disconnected the coolant and oil sensors?

Thanks in advance,
Chris