FadiCha

Great news, happy for you, people like you getting value from threads like this, makes it worthwhile to carry on with this journey. 

So, update: I received the capacitors today, and installed them in the inverter.. MIRACLE! The inverter is back to life like nothing happened lol. Can't believe a tiny capacitor can do that. I replaced the two 16v 1000uF ones only as I found it very hard to find any other capacitor replacements. There was visual evidence that the capacitors (C78 and C79) were both goners. 
@BritishRacingGreen and @Coulomb Thank you so much for your valuable contribution to this thread. Saved me from needing to purchase a new inverter just due to two small capacitors.

This type of content is really Golden!! One thing is to buy an imported product. Totally other thing to know the deep engineering behind such product. 
Living in a place like SA I have realised that one needs to be self reliant. Not reliant on any big company or establishment. @BritishRacingGreenyou are making the Voltronics machine open source to repairs & troubleshooting. Now only if you & @Coulombcould  physically be in the same place hacking these machines together. 
One of these days a Deye inverter & Sunsynk will enjoy this same reverse engineering. Can't wait for that to happen. 
Been great following this thread & I think it will remain a very long lengthy thread of Golden content. 

It means that the display MCU can't talk to the main inverter's DSP (the two computers can't talk to each other).
It's probably the issue that plagues this model: noise from the PV getting into other parts of the circuit. Sometimes it's the display, sometimes it's communications.
The solution seems to be a capacitor across the PV terminals, and/or extra metal .shielding. Newer models are modified to fix this. I believe that you can get this fixed under warranty, but of course that means a long delay and inconvenience if there was to be a load shedding.
If you're good with electronics you might be able to do it yourself, but this is a moderately dangerous procedure if you don't do it correctly. Use the following at your own risk:
https://powerforum.co.za/files/file/143-axpert-and-infinisolar-capacitor-modificationpdf/