So my truck wouldn't start saturday.

Put the key in ignition I keyed to run and the WTS came on and efuel pump turned on as well just like normal.
Any ways as soon as I keyed to start. It sounded like some sort of short and truck completely died no power what so ever even before it tried to turnover. I tried jumping my truck with no luck since I could not find my voltage meter at the time.
I gave up and tried on sunday morning, I found my voltage meter and read that the passenger side was a lil low at 11. Amps.
I tried jumping it and still couldn't get it to start. So I cleaned my connections and terminals. I let it sit for a good 20 mins. And she ended up starting right up. My terminals were not that dirty. So I drove the truck all day and it started multiple times perfectly.

Well the truck sat till Tuesday and I hopped in it and the same thing that happened Saturday night happened again. I keyed it to run and the WTS light came on and my e fuel pump started running. But as soon as I keyed to start the truck died completely even before turning over. Iread the amperage on the batteries at 12.50.

I should of inspected my grounds but I will do that when I get home. My chip shouldn't be loose I just re-installed it with duct tape a month ago.

 

Any other ideas other than to inspect my grounds which I will do when I get home. My fuses looked good as well.

 

When you say amperage you mean voltage, right. 12.5 is good, 11.0 is not. Either way, though, it's real hard to tell if batteries are good or not in the truck. Gotta take them somewhere to be load tested.

It is weird that the pcm dies when you turn it to start. I've had bad starter connections cause a no-crank but the pcm still stays on.

Definitely check all your battery connections and grounds - to the block, the radiator support and the fenders. Lots of important grounds up there. I know from very recent experience!

 

Well before it got pitch black I double checked all my grounds nothing was loose and looked good. I believe I found them all but probably not. Im going to take my batteries in and have them load tested. Would any of this relate to a faulty starter relay?

Today the truck lost its power to the pcm while the WTS light was on.

 

It really does sound like dirty or bad grounds. There's quite a few. Also check the positive side just for s&g

 

The fender mounted starter relay is the junction point for the rest of the truck to get juice from the batteries. I would check the nut on the side of the relay that has multiple wires going to it, to see if it is tight. Also check the cable that runs from the battery to the relay, to see if there is any corrosion on either end.

 

Good to know thank you. Yeah the nut was tight on it but I didnt see any corrosion.

I ended up going to the parts store after traffic died down both batteries passed the load test and I picked up a starter relay just in case.

Well the truck started right up with the new relay installed.
I should reinstall the old one to confirm my issue but im tired its cold I need to pack for the last weekend of pheasant season wish me luck guys.

And thank you once again for all the comments you guys are the best.

 

Well, I would call it good. Personally, if it works now, don't tempt fate a 2nd time.

Good luck pheasant hunting!

 

I would say you had a bad connection at the fender mounted relay, it doesn't take much corrosion to break the chain. By dismantling and reassembling, the connection was reestablished.
It also possible a connection at the battery was weak.

 

This is a more likely explanation than the relay itself. The circuits do not go through the relay, they just use that terminal stud as a junction point. So even if the relay were bad, it would only affect cranking the starter, it wouldn't cause a loss of general power. A bad connection there would do exactly that. 'Sall good, the OP now has a spare.