[Warning Light] Wiring ID

[RafM]

I have a Haynes manual with wiring diagrams but there is no key for any of the symbols shown although some things like ECU, ignition switch etc are labelled, also there are no wiring colours. Does anyone know where I can get any further info? 

My UREA light is on, Citroen said the system is working but the pump is not receiving any power and have suggested a broken wire/open circuit fault. They recommend changing the wiring loom in the entire engine bay!!!

I want to check for continuity along the relevant wires.

Thanks for any suggestions.

[oilyrag]

If the power source to the unit is obvious - ie a plug then you might try a separate lead, ignition controlled, with an in-line fuse direct to the plug ? This will verify whether there is a break somewhere and could even become a short to long-term fix.
Good luck!

[RafM]

It may work to see if the supply cable is broken (assuming the pump is 12v) But the signal to run the pump will likely come from the ECU I suspect. Could do with a factory level of wiring/control diagrams really to see how the system works.

[cancunia]

What year is your B9?
Can you post a picture if the Haynes diagram?
I may be able to find something on SEDRE, but the diagrams only go up to about 2011.