Peugeot 306 wiring fault, wire BB2 - Chaz

I have a 1996 306 D turbo and am having problems with the heater blower and heated rear window not working.

There is a wire labled BB2 which runs from the positive control unit next to the battery to the ignition switch. When I measure the voltage at the ignition switch end (Before it actually goes htrough the ignition switch) it is low, indicating a break in the wire somewhere.

Can anybody tell me where this wire BB2 is routed so I can try and find the fault.

Thanks
Peugeot 306 wiring fault, wire BB2 - IanT
The control unit is under the big plastic cover on the nearside wing. There are also several 30 amp fuses under this cover - I don't think any of these is for wire BB2, but it's worth checking them just to be sure.

BB2 passes with the cable bundle through the bulkhead and into the dashboard on the left side and emerges on the right side. So any attempt to follow it will be a bit difficult. If you read Haynes's instructions for removing the complete facia assembly, it refers to a "main facia wiring harness connector" located in the scuttle under the windscreen wiper motor. But it doesn't tell you what cables it connects.

My choice would be to run a new cable from the control box to the ignition switch, fastened to BB2 at each end. You would have to make your own route for the cable, which would be more vulnerable than the original, so you should fit a suitably large in-line fuse (10 amps?).

Ian

PS I would be interested if anyone could tell me what the control unit actually does!