I keep getting these three codes on my 1999 328i.

P1397, Exhaust Cam position sensor

P1529, Exhaust VANOS Solenoid Electrical Fault

P1622Electric Thermostat Control, Final Stage

I started by replacing the Cam position sensor. ALL THREE codes came back immediatly.

Is there something else that could cause this combination of codes?

Can I test the input and output voltages to the cam position sensor? Would I do it with the key on but engine off?

What if I turn the key to the on position with the engine off. Then check the input voltage in the connector with it disconnected from the position sensor.

Does anyone know which of the 3 pins is input? What should the input voltage be? Anyother ways to test?