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Howdy guys and gals,

This is just some insight on a problem I was trouble shooting for a couple months, and I'm just making this post because I couldn't find anything in the same realm as my problem on a prior post.

So started having super weird electrical issues one day when i put on my cruise: cruise light didn't come on, RPM gauge starting dancing from 0 all the way to red line ridiculously fast, blinkers didn't work or light up on the dash, and I got a message saying check washer fluid (hazards still worked). I immediately thought it had to be a relay, because multiple functions just shit the bed all of sudden. I shut my truck off when I got home from work, cycled just to on to see if my blinkers would come back and they did, but check engine light came on as well. P0650, did a decent chunk of research and it seems everyone's fix was different, but definitely wiring or electrical related. My truck is approaching 280k so I figured it wouldn't hurt to just replace the three main fuses so I did, reset the code and off I went.
Again 2 weeks later the identical things happens, except this time the tach went completely out and all dash indicator lights. I opened the fuse box up pushed down on all the relays and twisted them a little and pushed down on all my small fuses. Nothing felts loose, but sure enough everything came back on with a P0650 code. This repeated itself now at anytime or speed or engine load about once every two weeks. Did some more research, still couldn't find anything on ANY forum that was giving me any lead. Just for shits and giggles I bought 3 of the smaller relays and replaced the HDLP-high, HDLP-low, and F/PMP smaller relays, not really expecting it to work but a shot in the dark more or less.
However, when i was trying to jiggle out the small relays, I noticed one of my smaller ECM fuses was literally jiggling in place as I was doing this. It was at full seated depth just shaking ever so slightly in place. Just out of curiosity I started my truck up, yanked the fuse while it was running and boom, problem repeated it self exactly as it did before.
Sure enough I looked inside and noticed the pin slots inside were pressed really far open like someone had shoved a Tap-a-fuse or something inside hard enough to spread the fins way out. I took a pick out and carefully pressed the fins together as gently as I could so It would hold the fuse in place and haven't had the problem arise again in over a month. I guess I would have located the problem quicker but in my mind if an ECM fuse is blown I would expect something more serious like the truck not running at all or a power cut of some sort. Thought I would just splurge this out here so I can save someone else the headache and worry.

TLDR: If you are having tach, blinker, P0650, and/or the "check washer fluid" problems, start your troubleshooting at the #4 fuse under the hood. Hope this saves someone some time.


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