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Mike, Technician
Category: Jeep
Satisfied Customers: 39198
Experience:  Tech Expert
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I have jeep wrangler crd sport unlimited (48K miles). The m37

Customer Question

I have jeep wrangler crd sport unlimited (48K miles). The m37 fuse (10amp) blows when I apply the brakes but not every time.
Submitted: 3 years ago.
Category: Jeep
Expert:  Mike replied 3 years ago.
Hello and Welcome -

My name is MIKE - Im happy to help you -

Sadly this is a common fault on these models - with different causes. As you may well know, that fuse covers several circuits - so what you generally need to do to find the cause of the fuse blowing , is disconnect the items on that circuit - and see if the short, thats causing the blow, to go away. With the ign on / engine running - give all these wires a tug / shake - that often helps to find the short.. If the engine stops suddenly, you know you caused it to short - and blow the fuse... so you know you are in the right area.

The trouble is with yours its not very serious at the moment so it can be hard to find - because the short has to be there - to find it. Thats why the dealer / diagnostics didn't find it - it wasn't happening thats why you need to check the wiring as above.

So what I would suggest is to carefully check all the wiring - the looms - check in the engine bay / around the engine - under the dash by the pedals especially and steering column and under the seats / frame etc..

With movement of the car, the wires run and get worse - so that if thats it, it will bare a wire altogether and you will have a permanent blowing fuse - ( that does make it easier to find actually - but you need to progress as above at this point - )

This is painstaking / time consuming work - as you do need to be very careful so you don't miss the fault - Again - you need to follow the cabling through as above - twist the cables over to check for damage to the underside...and working as above, you have every chance of finding - and then of course, curing the fault..

We can progress with component testing later if needed but thats the way to go now on this one given the stage its at -

Let me know if you need anything more on this at all -

Please do click on the "OK rating to Excellent ratings" service for me now, Thank you for that... and you can get back to me anytime if you need / wish..

Very Best Rgds, MIKE.

Please note, you are rating the content of my "answer" - my help to you - not the "system" which can experience delays etc which are not under my personal control -or delays caused by "time -off" which we all have on occasion - Thank you.

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