Just bought a used 2001 Dakota sport,4.7,4x4.manual transmission. Drives and shifts fine,lights on dash switch light up for two wheel drive and four high, four low light even comes on after blinking for a minute or so but does not engage transfer case for four wheel in high or low. Where is a good starting point to look? I don't see a shift lever on case. Only what looks like an electric solenoid or motor in the side.