No, it hasn't broken, this is my own fault

I thought I'd disconnect the MAF sensor to see if it had any effect on fuel consumption. It didn't appear to. It did affect the engine performance though accompanied by the 'reduced engine performance' message. After my trial it was reconnected. The problem now is I still have reduced performance along with the message. I thought it would reset itself when the vehicle was stopped and restarted. Will it need to be hooked up to a diagnostic tool to clear it?

......and has anyone bought or used the icarsoft i930 diagnostic unit? Loads for sale on eBay at about the £90-£100 mark and I was wondering if it's any good  It better to laugh than cry

Disco sport 2016 HSE
FL2 2011 XS gone
Disco3 2005 Tdv6 SE gone
Disco2 2000 Td5 ES gone
Disco1 1998 V8iS gone
Disco1 1996 3dr 300tdi gone

What you could try is disconnect the battery leave it overnight & see if it resets (hard reset)

you will need to clear fault with diagnostics tool 2014 SE Loire Blue SD4 Auto (MY15)
Gone - 2011 GS Baltic Blue, Retrofit Electric Leather, Side Steps, 19"SC's, Roof Rails, TT Sat Nav Mod, Retrofit Premium Audio, Retro fit 2013 Xenons with DRL & Sig Strip (Clutch at 47k)
Gone - 2007 GS Narvik Black, Privacy Glass, 19" SC's, Side Steps,Roof Rails, Roof Spoiler, Lamp Guards, Retrofit Electric Leather (Clutch at 115k)
Gone - 2007 SE Santorini Black (Clutch at 120k)
BT IID (best money ever spent on a car)

Thanks for the replies

I think I need to buy a diagnostic tool  It better to laugh than cry

Disco sport 2016 HSE
FL2 2011 XS gone
Disco3 2005 Tdv6 SE gone
Disco2 2000 Td5 ES gone
Disco1 1998 V8iS gone
Disco1 1996 3dr 300tdi gone

I have had a couple of problems recently with a DPF sensor which kicked off the "reduced performance" message. I called out LR assist and the guy said that often the message will go after a few restarts so he did just that and it made no difference. The next morning the message was still there but after driving for a little while it went away. In summary it looks as if it clears itself (especially if the engine is not actually in that mode ie it will do more than about 2.5k rpm).
In my case the message eventually came back as the sensor was causing the problem but you should be OK. 3 x FL1 2 manual + 1 auto
5 x FL2 4 manual + 1 auto
Now Discovery Sport P250 MHEV SE

After leaving the vehicle for about 36hrs the fault had cleared itself

I have however bought an icarsoft LRll diagnostic tool which I am very pleased with. It reads and deletes DTC's from loads of Landrover & jaguar vehicles plus it is capable of resetting service lights, SAS, EPB and DPF regeneration.

I think these are an essential tool with modern vehicles and especially Landrovers  It better to laugh than cry

Disco sport 2016 HSE
FL2 2011 XS gone
Disco3 2005 Tdv6 SE gone
Disco2 2000 Td5 ES gone
Disco1 1998 V8iS gone
Disco1 1996 3dr 300tdi gone