Geoff West wrote:

Thanks Jaygee, i've been thinking that. Would a generic one do the job, or would it have to specific to RR? Any recommendations ( at a reasonable price)?

Just buy a GAP IID Bluetooth from Island 4x4 and be comfortable in the fact it’s the best one for your needs and very strong resale value. I won’t drive mine anywhere without it in the glovebox. Please heed the advice; most of us on here have been around the block on these vehicles for a long time  Gone to a good home: 2011 4.4 TDV8 Vogue SE Buckingham Blue with Ivory and clear glass = "Rory"
2025MY Defender D350 90 in Silicon Silver on coils
1974 Series 3 Lightweight = "Millie"
Many, many other Landies over the years
My preferred specialist: www.glenrands.co.uk
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Thanks Jagracer, I'll check that out, although I'm thinking that if faulty multiplug blocking electrical signal to the fan, it would NOT run rather than running all the time? I suppose it depends whether the default setting for the fan clutch is locked or unlocked.
I'm also wondering if the faulty ambient temp sensor is playing a role in this,(?) although I've read that it only "talks" to the aircon.
I'll definitely have all connections checked for corrosion, as you suggest, as I also have an intermittent fault on rear parking sensors and I'm sure that must be dodgy connections.
Thanks.

I had a similar problem (see my post), replaced viscous fan and all is good. Also check the fan fuse in the engine bay and replace thermostat. It could be that the thermostat is stuck closed preventing the engine from normal operation