Camshaft position sensor question

[Themoog]

I've been getting a code on the X5 stating inlet camshaft control bank 2.. 022 on my code reader.
Anyway, yesterday I thought I'd whip out the vanos solenoids to give them a clean out and swap out the timing chain tensioner too (4.4).
I noticed that the cam sensor on the left side - looking at the engine from the front, was an aftermarket item with no brand or part number. The right side sensor is original BMW.
Curiosity got the better of me so I got my Fluke out to check the resistance on the pins of the sensors.
The BMW one had a reading of 1.463 but the aftermarket one was circa . 650
One would expect the two to be the same but I don't know what the figures should be.
Does the aftermarket sensor have a duff reading and is on its way out?
The solenoids were tested and worked OK.
Getting the new chain tensioner in was another story..
Looking from outside the car at the engine what side is bank 1?