This is from a Fiesta - but may be correct as Haynes Manual is same for both.

There is also a fan relay in the internal fuse box, but should be identifiable from the sticker on the back of the glove box.

The relay in the engine is for the "high speed", bypassing the slow speed resistor

On 6/27/2019 at 1:20 PM, Paulkp said:

This is from a Fiesta - but may be correct as Haynes Manual is same for both.

There is also a fan relay in the internal fuse box, but should be identifiable from the sticker on the back of the glove box.

The relay in the engine is for the "high speed", bypassing the slow speed resistor

Thank you so much, Paul. I haven't had access to the car for a few weeks as my son was using it, on strict instructions not to use the air conditioning. Picked it up this morning, found your post, took the cap off the relay box, started the engine, ran the air conditioning, waited until the fast fan kicked in, and then pulled relay number 2. The fast fan immediately stopped, leaving just the slow fan running, so stopped air conditioning, then stopped the engine. To my surprise the relay was hot, one of the flat metal pins at the bottom so hot I couldn't touch it when I had just pulled it. For comparison, I pulled the two other relays and they were cool. Guesing something like corrosion or heat erosion inside the relay causing it to make poor contact, and sometimes stick instead of opening. Am now about to order a replacement using the part number of that relay.

Good to hear your progress - hopefully that will sort it.

I had this on ford fusion 2010 1.6tdci titanium. Fan overunning high speed. My fix was the high speed fan relay. I also have A/C which may make a difference. It's in the small box behind battery. Fiddly tabs to remove the cover. I have 3 relays. I pulled each one at a time when the fan was overunning. On mine it's the grey one. Part no. 5M5T14B192EA fomoco brand made in Portugal. Easy to find on eBay... Suggest an original spare if possible. I originally opened mine and cleaned contacts with fine emery and replace,l am see I'm lasted another 6 years. Have now had to replace it. Hope this helps.

8 minutes ago, Jasper520 said:

Hope this helps.

You do realise it's 9 years since the original poster had this problem ?

.... and 4 years since John had an issue 🤣

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