2009 expert 1.6 help no crank no start intermittent

[phdowson]

Please help as this issue seems to have hundreds of different results on internet searches.
My expert has been intermittently failing to crank for months. I turn the key and get a faint click from or around bsm under the dash. But no crank.
I have checked all fuses, all plugs stripped each fuse box out and checked condition of pins.
Then without warning it cranks and starts this often works for a day or two and the fault returns again.
I get the standard anti pollution warning on display.
I have connected my topdon code reader and it returns power latch relay codes and failure to connect to ECU.
The fuses under floor next to the battery have been wet on occasions but I'm not sure if they are relevant.
Can anyone offer some guidance please

[wheeler]

First thing you need to do is confirm if the starter solenoid is getting a feed when its not starting. Could just be a failing starter motor.