Fuse 18 keeps blowing

[pm254]

i have a 2017 and 2016 both keep blowing cabin fuse 18. bought both from auction. the 16 would start and run but the little fuse box under the hood had damage. i changed it out and it still keeps blowing the fuse as soon as the key is turned on. from what i see the wires are ok going to the box. what would cause them to keep blowing instantly

 

[J_C]

What is fuse 18 on a '16/'17 for? On my '14, it's the front blower motor, so I'd wonder if there's a problem with it, though it would seem pretty coincidental to have two vehicles which both have a blower motor problem simultaneously. Edit: Disregard that, was thinking of #18 in the under-hood power distribution box.

 

[pm254]

What is fuse 18 on a '16/'17 for? On my '14, it's the front blower motor, so I'd wonder if there's a problem with it, though it would seem pretty coincidental to have two vehicles which both have a blower motor problem simultaneously.

The interior fuse on 16 and 17 is for the ignition switch

 

[J_C]

Oh, I missed where you wrote cabin fuse because I read "the 16 would start and run but the little fuse box under the hood had damage. i changed it out and it still keeps blowing the fuse as soon as the key is turned on." so I was thinking #18 in the power distribution box.

#18 interior fuse box on mine lists a lot, keypad illumination, brake shift interlock, start button run indicator, PATS, PCM wake-up, and rear power seat enable.

Since your fuse 18 has a different function, I'd want a wiring diagram and what I have wouldn't apply to a '16-'17. Considering it's the ignition switch, I'd wonder about wiring getting frayed due to steering wheel tilt or chafing, or is the PIU ignition switch on the dash instead of steering column? If so then I'd take the ignition switch out and check for wear/damage and whether any special equipment was torn out and left behind a wiring mess.

You could check the '14 wiring diagrams in my sig or the workshop manual troubleshooting but there would be some guesswork involved too since it seems the circuit changed... but where the connector part # and wiring colors are right, the circuit is likely to be the same.

 

[t9087]

i have a 2017 and 2016 both keep blowing cabin fuse 18. bought both from auction. the 16 would start and run but the little fuse box under the hood had damage. i changed it out and it still keeps blowing the fuse as soon as the key is turned on. from what i see the wires are ok going to the box. what would cause them to keep blowing instantly

There might be an old secure idle tied into the ignition circuit that is shorting out to ground. Maybe the wires are touching from being cut or wired wrong when removed.

 

[t9087]

Fuse 18 is coming from “BM” to the ignition switch

 

[pm254]

Fuse 18 is coming from “BM” to the ignition switch

It’s the 3 prong fuse. It only blows on the right side

 

[Deleted member 380243]

i have a 2017 and 2016 both keep blowing cabin fuse 18. bought both from auction. the 16 would start and run but the little fuse box under the hood had damage. i changed it out and it still keeps blowing the fuse as soon as the key is turned on. from what i see the wires are ok going to the box. what would cause them to keep blowing instantly

Welcome! I hope you'll find the help you need!!!

 

[peterk9]

i have a 2017 and 2016 both keep blowing cabin fuse 18. bought both from auction. the 16 would start and run but the little fuse box under the hood had damage. i changed it out and it still keeps blowing the fuse as soon as the key is turned on. from what i see the wires are ok going to the box. what would cause them to keep blowing instantly

Welcome to the Forum.
You stated that the 2016 would start and run but then also said that the fuse blows as soon as you turn the key. So does that mean it runs with fuse #18 blown? Does the same apply to the 2017?

Peter

 

[pm254]

Welcome to the Forum.
You stated that the 2016 would start and run but then also said that the fuse blows as soon as you turn the key. So does that mean it runs with fuse #18 blown? Does the same apply to the 2017?

Peter

 

[peterk9]

No reply was entered with the quote.

Peter

 

[pm254]

Welcome to the Forum.
You stated that the 2016 would start and run but then also said that the fuse blows as soon as you turn the key. So does that mean it runs with fuse #18 blown? Does the same apply to the 2017?

Peter

It use to run. Now as soon as you turn the key on it blows the fuse. Same on the other explorer

No reply was entered with the quote.

Peter

neither will start. As soon as the key is turned the fuse blows. On both units

 

[peterk9]

It use to run. Now as soon as you turn the key on it blows the fuse. Same on the other explorer

neither will start. As soon as the key is turned the fuse blows. On both units

I wonder if there is a short somewhere. When these vehicles are decommissioned. the people doing the work don't always use the greatest care. I don't know if this issue would have set any trouble codes.

Peter

 

[Deleted member 380243]

It use to run. Now as soon as you turn the key on it blows the fuse. Same on the other explorer

neither will start. As soon as the key is turned the fuse blows. On both units

You can share codes here is okay! Or screenshots!

 

[t9087]

Fuse 18 is coming from “BM” to the ignition switch

17 and 18 share the same fuse but each is its own circuit (Left 17, Right 18). 18 power the ignition switch on the 2016 and 2017 PIU.

So remove the knee bolster and metal plate behind that. Inspect the ignition switch and steering column wiring. You’ll probably find old wiring shorting or wiring not heat shrink after it came out of service.

 

[pm254]

17 and 18 share the same fuse but each is its own circuit (Left 17, Right 18). 18 power the ignition switch on the 2016 and 2017 PIU.

So remove the knee bolster and metal plate behind that. Inspect the ignition switch and steering column wiring. You’ll probably find old wiring shorting or wiring not heat shrink after it came out of service.

I did that and nothin. I’m starting to think the cabin fuse box is bad. It started smoking today

 

[J_C]

Yes if it wasn't bad before, it or wiring behind may be bad now.

I hope you are replacing these blown fuses with major brand replacements, as it has often been discovered that generic chinese fuses do not blow at their rated current.