Hi folks,
In haste, as I've got lots to do before I leave home tomorrow morning for a few weeks...
Circuit 38, for a basic TDI (without a vast array of optional extras) feeds the following:
G22 speedo drive (top of gearbox)
N280 (from memory, is this the one connected to the aircon compressor?)
G65 (just behind the aircon radiator)
E87 (the climate control unit itself)
G266 (the oil level/temp sensor in the sump)
E3 (the hazard warning switch above the cup holders)
J500 (the power steering control unit, attached to the power steering pump)
If you've got heated seats or an auto-dimming mirror or factory telephone prep or OEM parking sensors, etc, then these are also fed from fuse 38. But, given that we've got two cars with the same problem, I'd guess it's a component that's common to all TDIs that's the cause of the fault. I hope I've listed all the possible culprits above, but in my rush I could have missed something. I doubt this is a wiring loom issue because a) they're almost unheard of and b) you've both got exactly the same problem. I could be wrong, of course, but I'd start by looking at the devices fed by fuse 38 rather than the wiring.
With a bit of methodical trial and error, you will find the problem. Unplug stuff, soak test, plug stuff in, soak test, etc. You may chew a few fuses in the process, but nothing that was made by man cannot be fixed by man.
Good luck!
Tom
PS: I'm almost totally booked-up for the next 4 or 5 week, but I am willing to have a go at solving this.