pulled codes on my kids' 03 Neon - 0340 and 0579

0340- camshaft position sensor circuit
0579- speed control multiplexed switch stuck/ rationality

car wouldn't start the other day and CEL came on. I found battery terminals corroded and spark plugs didn't look too good. Cleaned terminals and changed plugs. Car starts fine.

Speed control is inop.

I'm not sure what effect cam sensor is having on the car.
I saw another thread where sensor was changed and it created more problems.

Can anyone enlighten me on either issue? Let me know where the cam sensor is (and the "multiplexed" switch)?

 

Update: Still need help with the 0579 problem.

I bought the $25 O'Reilly AP sensor and installed. That got rid of the 0340 code. PITA reaching through AC lines and harnesses to get the four screws out. Take out battery if you're going to do this job. The wire harness to the sensor is also a PITA. Be sure to slide out the red clip holding the harness to the sensor. Next, lift the black tab on the harness connector and pull. Dirt/ grime/ heat sticks these parts together pretty good. I broke the black tab on mine but you can disconnect it with a small screwdriver (lift the tab up).

If you're looking for the sensor, it's about a 2"x2" black plastic square on the right side of the head as you're looking at the engine from the front of the car.

As mentioned, I'm not sure what the 0579 code means. Not sure where this "switch" is and how to unstick it. I thought the cruise was controlled by the ECM.

 

This is what I found for P0579: http://engine-codes.com/p0579_chrysler.html
Sounds like something is wrong with the wiring most likely. IIRC, there aren't a whole lot for the cruise control system.