How to wire up camshaft position sensor in lab environment?
Well, nobody else seems inclined to answer so I'll go a head and give it a shot.

This is a simplified diagram of your sensor taken from the schematic you posted:







simulate this circuit &ndash; Schematic created using CircuitLab

To test this on the work bench, you provide 12V on the pink wire and ground on the black wire.  Then you need a 5Volt supply, with its ground connected to the ground of the 12V supply.  Connect the 5V to the blue/black wire through a resistor - I'd probably start with a 10k Ohm resistor.

Connect the ground of your oscilloscope to the black wire, and the tip to the blue/black wire.

Now, move a metal object like a screwdriver or wrench around the sensor in the place where the camshaft would usually be.  You should see some reaction on the scope when you move things around.



There's not a lot that can go wrong here.

The options are as follows:


Bad wire.  Check all of the wiring for continuity.  Since you mention the 12V going from 2V to 12V slowly when you turn on the engine, there might be a problem with the 12V supply wiring. 
The sensor is bad.  If the wiring is OK, then this is the most likely problem.
ECU input is broken.  This is the most expensive problem, since the only real solution is to replace the ECU.  


Check the wiring and connectors carefully.  If they are OK, replace the sensor.  If that doesn't help, then the ECU is the only thing left.