Engine codes - P0837 & P0838. Is it my transfer case switch?

[ahjjones]

I've recently got these two engine codes, "P0838, and P0837. I found out they mean, "P0837 -Four Wheel Drive (4WD) Switch Circuit Range/Performance, P0838 -Four Wheel Drive (4WD) Switch Circuit Low". So, is my transfer case switch/sensor in need of replacing? Ever since I brought it I've gotten the part-time light on, even though it's in 2WD. I firgured the switch is the problem, since research brought it up as a common issue.

PS: I also have P1491, which I'm guessing means I need the radiator replay needs to be replaced, am I correct?

Thank you for your time!