There is a fat ground coming from the injector wires bundle on the driver's side, but it's attached to the a/c compressor bracket. I can see the old (empty) crimp still on the bolt in the correct location. Looks like the wire came out of the crimp, and someone crimped on a new connector-- but that made it too short to hit the correct bolt so they just landed it on the compressor. The battery engine ground is still correctly attached on the bolt with the empty crimp.

So, how important is this? To fix correctly, I assume I'd need to replace the entire wire bundle-- could I also just make a jumper to tie the current bolt and the correct ones together directly?

Now that I think about it, the nobus issue started happening a few months after my water pump seized and the serpentine popped off. Good chance that knocked the wire out of the crimp and the shop patched it up after they replaced the pump. There was a long delay between that fix and this issue, but the repair was in Dec when it was cool-- could be that heat makes ground issues more sensitive.

Back to the dangling body ground. I traced the two attached grounds on the same body bolt as the unfastened one. One appears to attach to the passenger side block, the other to the passenger side head. I can't find mention of any of the three in sec 8W.... I did go through all of the G1xx grounds and confirm they're all connected and tight.

 

I would have a close look at the moved ground wire. It *should* be ok there, so long as the crimp connector is good, and it is making good contact to the bracket..... not like the bracket is electrically isolated from the engine block......

 

Ohmed it out:

• 0.5 ohms from the substitute bolt to the battery neg terminal.
• 0.4 ohms from the correct bolt to the battery neg terminal.
• 0.4 ohms from the correct bolt to the substitute bolt.

Suspect it's a red herring. I might slap a jumper on there just for grins, but I'm going to keep looking.

 

How about from the wire itself to the battery negative terminal?

Wiggle it while testing, see if the reading stays consistent.

 

I had a no-bus a while back, it ended up being poor contact of the large plug in the dist block, the one with a single screw in the middle. Tried to tighten and it just strips out though I'm sure it's never been touched before.
I romoved the plug, sprayed the contacts with electronic cleaner, reinstalled and problem solved.
Might want to give that a shot if you haven't yet.

Other things I did was spray the plugs to the ecm with electronic cleaner.
Sand the ground connections on the firewall, ecm, and front chassis by the battery, remove the paint to bare metal.

 

Im curious, I just bought this truck and it came with a tuner. I was just messing with the tuner and no bus came up on the dash. What does that even mean? The truck has no problems but is this something to worry about?

 

What tuner? Doesn't matter really. What ever brand it is , return to stock . And start troubleshooting with out the tune installed. You might also want to check the IOD fuse on the side of the dash. (It has a special black plastic cover on it).

 

i had a truck come into the shop with that same issue. found there to be a whole lot of corrosion underneath the main fuse block in the engine compartment. cleaned it all up and resoldered some stuff ... worked out great!

 

Its a smartchips tuner. So when it says return to stock thats what I should do?

 

I know nothing about a smart chips tuner. I'd say yes though. If everything is normal without the tuner installed, (as in, not showing a "no bus") I would not use that tuner again. Hopefully it didn't screw up the PCM.