How to fix the 3.00 WiFi bug?

Seem this mentioned a few times I appreciate the 945lte is old but managed to get a new one cheap.

it came with some old software version 4xxx but WiFi worked fine, I updated to 17.xx and now doesn’t find any WiFi networks.

The WiFi version is 3.00, I’ve read 4.00 fixes the issue but how do I update the WiFi?