As in the thread title, I want to put Mjoll in light armor, but she's refusing to equip even superior, so I need to get rid of her heavy armor, any help would be appreciated, thanks for reading.

Anybody, please?

Open the console click on her and type showinventory then find steel armor or whatever on the list and type removeitem (code for item)

Thanks for the response, but her armor is not showing, I assume it's a hidden inventory in a dummy cell?

One last bump.

I suggest you change her Light Armor skill so it's very high and lower her Heavy Armor skill. That way, she'll wear the light armor as its armor rating will be higher than her default heavy.

I think that's setav lightarmor 100 and then do a setav heavyarmor 10 or something. Try that.

I'm gonna make another suggestion which you may not like: just dump Mjoll and get a light armor follower, like the miner girl at Darkwater or the Argonian at the same place.

dont use setav its bad. modav is a much better option.

Just to mention I've noticed with npcs you have to get really close to click on them with the console open otherwise it might be a wall or something, the name used to come up in oblivion and that made it easier. Might want to get close and try again.

She should equip Light Armour, but only if it's base stats are better than the stats of the armour she's wearing. I have been able to get Lydia, who has Steel Armour (31 Armour) by default, to wear Glass (38) and Scaled Armour (32), but not Elven (29). Also, Vorstag has the Heavy Armour skill but his default armour is Scale (32), which is Light, and he won't wear Steel (31), but will wear Dwarven (34). I think that Mjoll's default armour is Banded, but not sure, which means she should be able to equip Elven (Banded is 28 while Elven is 29).

Or maybe they were too low level for their Heavy Armour skills to make much difference when I was outfitting them.

Followers' default equipment is all sorts of messed up when compared to their skills. Seems like a major oversight, or Bethesda just didn't give a crap.

Point is, many followers come equipped with armor and weapons that doesn't fit their skillset. You need to use the console to see what their skills are (or look at UESP's list) and equip them appropriately.