Hi I got the check engine yellow light on out of nowhere.

I have had no starting issues, a few weeks ago when it was really cold the car was a bit sluggish when driving but that went, even in cold weather it started no problem, the glow plug light has never come on just the check engine light. I used a code reader and got the above code, having looked at google etc it says Glow plug control module is most likely, however, there is then total confusion over where it is, some say in the under bonnet fuse box and others say you have to remove the battery and battery tray and it's underneath there? It's a 1.6TDI SE Tech Greenline 2018 estate

Any help always appreciated

Cheers

Can anyone help with the above?