A couple of weeks back I came off the motorway and went into heavy traffic, only for my fiesta to get a temp warning light. Lo and behold, the main cooling fan stopped working completely, it didn't switch on at all.

So I proceeded to change the main fan relay and fuse. This seemed to have revived the fan, although it did rattle quite a bit. I thought all was well until I took it for a test drive. I noticed a burning smell, so I pulled over to investigate and found that the wires to the fan were literally burning. Upon further investigation, I found the new fuse I put in, rated for 40 amps (green just like the old blown fuse) had warped and burnt completely in its housing in the fuse box. I've replaced it with a new one and the fan refuses to come alive, I've changed the relay too just to be sure but the fan still won't play ball.

Could I have somehow damaged the fuse box? Or should I replace the main cooling fan before I check if it's a fuse box issue. The metal contacts inside the housing seem to have burnt, though I can't be sure.

Any advice appreciated. Thanks

Sounds like the fan had a partial short circuit and was pulling too much current and is now open circuit and dead. You will need to try a new fan after cleaning all the contacts as best you can, and maybe the wires to the fan need replacing if the insulation is burnt.

Ditto to Abraham

I would investigate and check all wires and replace before putting in a new fuse..

Sounds like the fan is damaged from getting to hot or binding and shorted the wires