2007 Mini Cooling Fan Problem for starters

[jrfinn33]

My Son picked up this Mini Cooper R56 2 years ago. Ran well and has been into BMW garages for service and checks. However this time his garage tells him his Cooling Fan needs further inspection.
I had a look and first thing I noticed R3 and R4 were missing from engine fuse box. So either they were not returned after checking or they have been missing for some time. I replaced them with 2 multifunction relays, no Joy. I connected 12v directly to the fan and it runs ok, so there is something in the circuitry at fault. Looking at the Haynes Manual there is not much in the circuit except the engine temp sensor which seems to be ok , the management system and the R3 relay.
Have tried continuity checking from connectors to fuses but not getting expected results. Im fairly clued into electronics and fault finding, so here I am looking for ides.
Can someone confirm if the fan should run when engine is started or do you have to wait until it reaches 109 degrees.
What is R4 used for, I dont see it in the Haynes circuitry.
Any support would be appreciated.

Jim

[woody]

On most modern cars the fan is controlled by the ECU via a relay and will have a separate fuse. Most plug in diagnostic readers will allow you to test run the fan. If you bypass the relay contacts and the fan runs you know its a control problem, if it doesn't the fault is in the power circuit .

[jrfinn33]

Thanks for your update, Unfortunately my BMW ODBii tester C110 does not appear to have the fan diagnostic option for the Mini.I have jumpered the relay contacts out but the fan does not start, even when the temp reaches 109 degrees. Im not confident that the wiring diagrams in the haynes manual matches what I have. Would anyone have the wiring details from the R56 service manual.

Regards,
Jim