Hi,My retained accessory power fuse was blown(50amp) replaced it with proper fuse next day fuse blew again.Would anybody be able to tell what to do next? I am assuming a short somewhere but don't know where to start.Thanks

 

Right off the hop it goes to the RAP relay and the power seat circuit breaker. On the RAP relay, it powers the coil+ and the normally open side of the switched contacts (pin 87) which only then provides the retained accessory power to the radio & windows for a period of time until you open the door. More often than not, the RAP fuse will blow due to a moisture problem in the driver side floor board shorting out the power seat wiring. I would pull back the carpet and have a look at the power seat wiring.

 

Checked under the seat everything looks normal I have owned the truck since it was new and have never had and leaks or moisture problems.Could it be the relay for the rap in the fuse box or the circuit breaker for the seats? Thanks for replying

 

It is possible that there is a combination of things happening all at once while in a RAP mode that is overloading the circuit, but that is somewhat unlikely. You could pull the power seat circuit breaker and test the load at the circuit breaker as you move the seat, same with the power window circuit breaker. You may need to use a DC shunt to test high current draws without killing your multimeter though as both of these circuit breakers are rated at 25A! Or you could do all of your current testing at the 50A RAP fuse if you were to pick up a 100A DC shunt like the one linked below.

- I put one of these on my 3D printer to see what kind of current draw I was seeing with my heated bed & hotend and to see if the combination was causing any voltage drop. I am an information junkie. I liked it so much that I bought another one to build into a test tool, but it found its way into a drawer out in the garage and I haven't gotten around to making an enclosure for it yet.

Or if you have a current clamp for your DMM and can locate the appropriate wire for the RAP circuit, you can monitor the current that way, but you'll go through a few fuses if it takes too long to find the culprit.

 

Thanks not really good at electrical things and I don't have any testers.After checking under the seat I had heard someone mention the kick panel decided to check there was 2 orange wires going into the under dash fuse box attached to a plug in the fuse box marked power seats.I traced them and as soon as they came out of the fuse about 6 inches down both wires where worn with bare wire showing.Spliced them together and plugged it back in need to get a 50 amp fuse and test to see if it blows.Will let you know.THANKS

 

If you found bare wire that could touch metal or a grounded wire, I'd say you likely found your problem. Good job!

 

So after over a week fuse has not blown and everything is working perfect.Thank you for replying and all your help