I've posted in other threads about problems with the CCM on my Passat. I still haven't resolved these yet, but I'm posting this question about the wiring to the fuel filler cap, as the circuit diagram in Haynes doesn't explain how the CCM is involved. I'm a bit confused!

The diagram shows the filler cap solenoid getting its live feed from the fuel cap switch. This in turn is fed from a star point, which in turn is connected to a fuse (F36, 15A). The fuse goes right back to the battery 12V.
The CCM only seems to be involved with the illumination of the switch. It feeds a bulb that sits in the same housing but is electrically separate from the switch circuit.

So what I don't understand is why when the CCM is faulty or removed (or the wires to it are damaged), this stops the fuel flap release from working.

Maybe the simple answer is just "Haynes is wrong"!

Does anyone have (or know where to find) a decent wiring diagram that covers the CCM for this model?

I was thinking of splashing out on a Bentley manual set as these seem to be more detailed than the Haynes ones; but as I'm currently unemployed, I don't want to spend this sort of money on a blind purchase without some recommendation. Has anyone used these manuals for electrical repairs, and can they recommend them?