003 Deville dts trouble codes

[purelux]

2003 Deville warning problem?

P0386. And p0340. Its for the camshaft and crankshaft sensor. I'm looking at buying the car and wasn't sure if this was a big or expensive problem to worry about. The seller says he thinks it came up after he had the battery replaced.

 

[purelux]

I now own the car, checked and cleared the codes, only drove a few miles but so far the check engine light hasn't tripped again. However I have a warning to check coolant level, I figured it was just low. However I checked and the coolant is nearly to the top of the resevoir. Does anybody know if the sensor can tell if the coolant/water mix is off or if it just checks the amount of coolant.