I understand you tested the sender and the gauge "on the bench" and the sender made the gauge read as it should when float was articulated. I got that.
Now:
Let me know when the gauge works when mounted in the cluster and test ground on cluster ears. Cluster NOT in truck. Sender operating the gauge. This would still be a "bench test". Stop there and report. Still can't tell if you got there or not. As you can see DADS50 is not sure either. STOP installing anything into truck UNTIL this test is successful and you have reported.
Just to say it one more time, Test the gauge while mounted into cluster with cluster REMOVED from truck. Test gauge using sender, with ground wire clipped at each ear, one at a time and report when that test is successful on all ears and STOP. Make sure you follow this exact test. Then wait for the next phase.
All you have to do it follow instructions. We will get there faster. You are holding this back by not following one simple test and reporting. You go on and on about other tests you are doing and removing this and that. Please stop doing that.
We are making sure that the cluster itself is carrying ground from the gauge to it's mounting. When it does, over and over on every ear, we will advise next step.
It sounds like your step three is what I am saying and it did not pass but not sure of the exact setup of test, not sure each ear was tested, not sure if other end of ground test wire was to the battery.
DADS50: There is only one discussion on the entire WWW and it's on Stovebolt, regarding how gauge is actually grounded. You were posting on it. It seems like the consensus is that the center slug or solder bump is not supposed to touch anything and has a clearance hole between the stud holes. This allows for only the "ground plate" to touch the inside of can. Which is a good thing. This ground is never discussed by trouble shooters. All anyone ever says (like me) is gauge needs to be grounded. The can and the plate need cleaned to bare, but it does no good if they don't touch tightly or cluster can "oil cans" going down the road. Every other ground place regarding this ongoing fuel reading system ground issue, that many have, can be screwed and bolted and crimped and cleaned and sanded and will become perfect, except this.
In my opinion, in an effort to get good ground contact, the nuts are sometimes over torqued causing other troubles. Like twisting the gauge guts or shorting something out on gauge. In my opinion If the can is bent away, or warped, it will not allow gauge to ground and finding that anomaly can caused some serious headaches. A couple of well placed rivet heads on can might help.
I am just think about this without ever having an AD truck because I like to find and help fix. Chris, this could be your problem.
