I noticed my aircon was not working when the car was at idle (sitting in traffic) and decided to get the aircon recharged, this did not cure the problem.
I read Alex's post about the Cooling Fan Module and tried checking the contacts , no change!
I bridged out the Module by connecting the Positive and Negative input tabs to the corresponding connections on the Fan motors and they both spooled up with no problem (proving the fans are not at fault).
I acquired a used (MY2014) Cooling Fan Module and fitted that, No Change.
So, How can I test to see if there is a signal coming from the Power Control Module to the Cooling Fan Module?
Incidentally, I have checked the signal wire is not broken using a multi meter.

Any thoughts on how to proceed will be gratefully received.

Weyboat

Looks like this one has us all foxed!
Does anyone know where I can buy a new Cooling Fan Module?

http://www.freel2.com/forum/topic19017.html FL2 MY10 TD4 GS traded in at 2 years
FL2 MY13 TD4 GS Current

Thanks @Yorky Bob
I have looked at the ebay seller but when I looked at the feedback left by buyers of this item, I noticed a couple that had to return them as faulty..
I also notice that @Northsea Medic had a good outcome and recommends him, so as I cannot figure out how to test the signal to the module, I will just have to try buying another with fingers crossed..

Made some progress with testing the Electronic Fan Control Module (EFCM) thanks to some advice from the guy that sells them on eBay.
The EFCM is controlled by the use of Pulse Width Modulation (PWM) sent from the Engine Control Module (ECM).
To test the EFCM, I cut the signal wire and connected a short length of 0.7mm cable to the end of the cable that is attached to the plug (Not the end that goes to the ECM!), I then emulated a pulse by tapping the other end of the wire to earth.
When I say tapping I mean touching the cable to earth and lifting off repeatedly (tapping) after a few seconds the fans started working and as soon as I stopped tapping the signal wire to earth, they stopped spinning.
This confirms that the EFCM is not receiving a pulse signal from the Engine Control Module..
I now need to work out what signals the Engine Control Module needs to receive in order to initiate sending a signal to the Electronic Fan Control Module.
Any ideas guys?

Firstly, have you tried connecting to a diagnostic tool to see if there was a DTC for the EFCM?
Secondly, sometimes if a module looses communication with a slave module and you replace the slave module, the primary module (PCM) may need to be reflashed with the new module connected to re-establish communication
Protocols.
I'm not 100% sure in this instance but I've seen this with other systems in the car, particularly LIN's.
Possibly requires a "entire vehicle reset" to re-establish communication. Reflashing the PCM is a fairly specialises job best suited to a dealer with correct hardware/software.
You may also want to verify that the 2014 module and 2010 modules are Compatible?
There is a raft of different fan specifications and settings within the vehicle CCF for the fan system.
Electrical and CCF systems are different in MY13 onwards for L359.
Confirm 100% module compatibly would be my first step! MY15
Tyre Pressure Monitoring System (TPMS)
Surround Camera System
InControl Apps soon to be replaced with CarPlay (WIP)
Meridian Premium Surround Sound
Digital Audio Broadcast
Timed Climate
Cruise ECO Data
Follow Me Home Reverse
Extra Features Menu
Picture In Motion
4x4i screen (WIP)
Digital Broadcast TV
Meridian Rear Media with WIFI
Factory Powered Tailgate
Blind Spot Monitoring (BSM)
Reverse Cross Traffic Alert (RCTA)
Electrochromatic Wing Mirrors (WIP)

Thanks for the info @Stuartc
I did attach my JLR Mongoose which gave me a DTC P0480-00.
I also cleared all DTC's and did a full vehicle reset but they did not help.
So I took the 3 plugs off the ECM and using my workshop manual wiring diagrams determined that there were only two 0.7 Violet cables running from the ECM, one to the Camshaft Position Sensor and the other to the EFCM.
Using a fine needle pushed into each of the cables at the ECM end of the cable I tested for continuity at the Camshaft sensor and the EFCM.
The result: continuity was confirmed to the Camshaft Sensor but not to the EFCM, this test also allowed me to distinguish which of the two 0.7 Violet cables fed the EFCM.
Next I ran a patch cable from the ECM to the EFCM and tested the fans with the air con working, Bingo! they spooled up at low speed..
So it was a broken wire in the loom somewhere (I did check as far as I could for a broken wire, but could not find one)
So, I have just spent the last 2 hours neatly running the patch cable along the side of the existing loom with the aid of some cable ties and insulation tape.
All working again

Haha, Bingo!
Well done, good that it was a simplish fix  MY15
Tyre Pressure Monitoring System (TPMS)
Surround Camera System
InControl Apps soon to be replaced with CarPlay (WIP)
Meridian Premium Surround Sound
Digital Audio Broadcast
Timed Climate
Cruise ECO Data
Follow Me Home Reverse
Extra Features Menu
Picture In Motion
4x4i screen (WIP)
Digital Broadcast TV
Meridian Rear Media with WIFI
Factory Powered Tailgate
Blind Spot Monitoring (BSM)
Reverse Cross Traffic Alert (RCTA)
Electrochromatic Wing Mirrors (WIP)

Thanks WEYBOAT you were spot on with your analysis of your fan fault. Just followed your tests and restored my fans back to life, I also had a broken wire. To help further the fan control module violet wire is in the far left hand ECM plug looking from the front of the car at pin number D4. The camshaft position sensor wire is in the middle plug at pin A1. Like you I only found 2 Violet wires. Good stuff.

I thought that info might help someone out one day

Yes, had the same problem and it was that purple wire - apparently quite a common problem with the earlier models - must have been a brittle batch that they used. Tattoos - Why would you choose to look like the wall of a public toilet?

I appreciate that this is quite an old post but I have the same issue with the violet wire. Would I be right in assuming that you have to remove the windscreen scuttle to get access to the ECM plug? I can't find any details anywhere on how you remove this. Many thanks.

Ours jtwas broken at the fan end. I now have a Santa Fe so can’t have a peep and send you exact location. Tattoos - Why would you choose to look like the wall of a public toilet?

Many thanks for this advice. I carefully unwound the insulation starting at the cooling fan end until I found the issue. The violet wire had been damaged close to the lowest tie by the fan. I was able to strip and solder to repair and both fans now work as they should.

Well done, it would appear to be quite a common fault especially near to the fans Tattoos - Why would you choose to look like the wall of a public toilet?