Recurring blowing fuse.

[Mart8888]

Hi, 

I have a 2018 ford edge st line and fuse 23 for the moonroof and drivers side door module control keeps blowing, the airbag warning light keeps coming on but it goes off again once the car is turned off and on again, I have taken it to the garage and they found an alternator fault and replaced it, however the fuse is still blowing and the airbag warning light still comes on and off at random, any ideas please? 

Thank you

Martin.

[unofix]

5 hours ago, Mart8888 said:

I have taken it to the garage and they found an alternator fault and replaced it,

Was that free of charge or did you pay ?

Just wondering what the alternator had to do with the faults you are reporting.

[simonb65]

12 hours ago, unofix said:

Just wondering what the alternator had to do with the faults you are reporting.

Exactly! They need to disconnect all the modules that come off that fuse, one by one, and see if the problem persists or which one makes it go away, then focus on that. If it still happens with all ECU's disconnected, then there is a harness fault somewhere! It's not difficult to find faults that draw high currents, but the alternator has zero to do with an individual fused circuit!

[Mart8888]

21 hours ago, unofix said:

Was that free of charge or did you pay ?

Just wondering what the alternator had to do with the faults you are reporting.

Hi, this was replaced under warranty. 

[Mart8888]

9 hours ago, simonb65 said:

Exactly! They need to disconnect all the modules that come off that fuse, one by one, and see if the problem persists or which one makes it go away, then focus on that. If it still happens with all ECU's disconnected, then there is a harness fault somewhere! It's not difficult to find faults that draw high currents, but the alternator has zero to do with an individual fused circuit!

Hi, thank you, they said they found the alternator was faulty as I could smell intermittent burning smell along with the intermittent airbag light and intermittent seat belt chime going off. 

[unofix]

32 minutes ago, Mart8888 said:

they said they found the alternator was faulty as I could smell intermittent burning smell along with the intermittent airbag light and intermittent seat belt chime going off

Well if they want to replace the alternator for free then let them !! but what that has to do with the price of fish is a mystery to me?

The burning smell is probably the real fault that keeps blowing the fuse. When alternators have a fault they almost always put the battery charge light on, not airbag and seat belt lights.

 

[Mart8888]

Ah OK, many thanks. 

[simonb65]

On 4/13/2022 at 8:25 PM, Mart8888 said:

I could smell intermittent burning smell along with the intermittent airbag light and intermittent seat belt chime going off

Sounds to me like a pin in a connector has become loose or high resistance and has possibly melted the connector housing. If you get an airbag/seat chime, then I would suspect the ECU under the seat that handles the side airbags, seat belt tensioner and seat occupancy switch is the culprit. Older models used to have a single ground wire into that ECU which used to burn out due to current draw, so later models now have 2 ground wires into it. Not saying its the same issue, but the symptoms sound similar! That would also be blowing your fuse if that ECU is supplied by it.  

Not on an Edge (still Ford though!), but this link is a classic example of loose pins and what happens ... https://www.f150forum.com/f118/melted-heated-cooled-seats-connector-468450/