No power after reconnecting battery

Let’s us know what 4wp or the battery tester says.

Just don’t connect a 16.6 v battery to your truck. You’re going to keep blowing things.

 

yea, that became painfully apparent yesterday afternoon...

 

just got back from 4wp. Amazon still hasn't delivered the fluke.

battery i use as the main measured 12.7. battery i use as the secondary measured 12.9. so, it's not the battery. something else is amiss.

none of the dual battery system components are connected so the blue sea ACR is not in the mix. solar system is also disconnected.

the one thing i had to do was extend the ground cable from the fuse box. it was about 4" too short to reach the neg terminal. all other cables are the same as when the dual battery system was in place.

i just picked up 2 more main fuse links from the dealer. i really do not want to buy another one.

at this point, i'm not sure where to start looking. the skies are about to open up so i'm not going to be able to do much this afternoon. will continue to dig and verify all connections tomorrow.

 

If you're blowing main fuses you have a short somewhere. KISS and start from the positive battery terminal and visually check every connection all the way back to negative post. Anything you took apart and re assembled, take back apart and check them again. If you do all of that then put the main fuse back in.
Pull the fuses for the lights that are dim before you do any of that.

Try that and then post back up, if it doesn't work then we can go to the next step.

 

I'm with @rockmup - keep it simple. If the battery is confirmed ok you need to start tracing cables.

I would start by checking continuity because even if your tester isn't showing volts properly continuity is easy to test. Look specifically for continuity where there shouldn't be. Make sure all doors are closed, all lights are off, etc.

Start with the battery out and the main fuse still out. Do a simple continuity check from the positive cable to the negative cable. If you have continuity, you have short before your fuse and you know where to look.

 

If your blowing the main fuse link, the short is after the link. Check continuity on the load side of the fuse link to battery -, it should read very low. If so, disconnect the wires coming off of the fuse link, separate them and check each individually. This will tell you which wire is causing the issue and should make it fairly easy to find the cause. I’m an e & I tech with 37 years experience. If you need help, pm me and I’ll do my best to walk you through it.

 

Yup - you're right. If it would have been before the fuse link it would have blown the battery.

You've got a great offer here @smslavin - take him up on it!

 

Hope you're back up soon @smslavin ! In for the resolution

 

Umm. Unless something is wildly different on 3rd gens, there is no ground cable from the battery to the fuse box.

This cable to the fuse box is a positive cable:


One ground to the inner fender, and the larger ground cable to the engine block:

 

yes. you are correct. i'm kicking myself right now. that is the issue. thank god for fuses.

i'm just going to sit here and continue my self-flagellation...

 

appreciate your offer. thank you.

 

Congrats on finding it.

 

So you got your truck running again?

 

Glad you got it, now go drive your truck!

 

Careful. If self-inflicted misery becomes your “thing”, you might just end up in an F150.

Now, are you certain those fusible link blocks you replaced are actually blown?

 

it's been my thing for a very long time but i learned my ford lesson with a saleen mustang i had many moons ago. never again.

yes, the blocks are blown. each has a little scorch mark and the link is severed.

also, fyi, the guy in the video posted above about removing the link did it all wrong. there's no need to hack apart the fuse box and drill a hole to get the main fuse out. i'll take some pictures and do a little write up.

 

yep

i wish i could.

thank you again for your offer of phone support. much appreciated.