You don't really need a diagram mate, get the bits below (or similar), I got my bits from ebay.

BMW AUX TV input lead BMW AUX AV INPUT/OUTPUT LEAD
Ipod AV connector : AV CABLE, TV Lead for Apple IPOD
RCA Av lead : 5M Triple 3 X RCA Phono AV
RCA Joiner: Triple RCA Phono Coupler

Then Install the BMW av lead between the cars loom and the TV module, connected the 5m triple RCA lead (red,white and yellow and ran it down the side of the car to the glovebox) and connect the coupler to it then the ipod (via the av lead).

I'll have a go at a diagram, give me a minute, here yer go.

__________________
Sept 03, M3, Silver Grey. Retro-fits: Modded Mk4 DVD Drive, OEM Bluetooth, VR Control, Rainbow Speaker Upgrade, Sony SOT Amp, HK Sub, CCFL, Intravee II, NightMode.