Quote Originally Posted by fred_dot_u View Post
I don't think your heart needs to sink, as you've provided a focus, narrowed things down nicely.

If the results of moving the "bad" sensor to the other side is that it suddenly becomes "good," you won't have too many variables to address. Making a guess on your connectors, I would suggest to examine that all leads of the specific connection to ensure the tiny metal prongs inside the plastic housing are pushed fully into the housing. The metal prongs are slightly spring loaded and the back side has a finger that sticks up in the opposite direction. When the prong is pushed into the housing, the finger pops up into a recess, preventing back travel. If the finger doesn't get fully into the recess, the prong can be pushed backwards when the connection is made.

If that doesn't solve the problem, you could have a cold solder joint. Those can be visibly obvious but can also be invisibly "un-obvious" and require a touch with a hot soldering iron to resolve.

It's best if you can identify the specific wire and the contact points at each end. It's apparent that the module assembly is in acceptable shape if you can move it completely from one side to the other. That leaves the connector into which it plugs (or is it a sub-board) on the way to the main board?

More details about the cable routing and connectors involved would be helpful. Photos might be helpful but not necessarily, as it could be challenging to get suitable detail amidst a bundle of wires. Photos of the connectors involved in the circuit would be good.
Fiddling seems to show the bad connection is just inside where the wrapped bundle of cables enters the case. Immobilizing all movement of the wires within the cable bundle at any point close to the base unit almost halts the blinking out of the LED even with lots of fiddling downstream of the immobilization point whereas any slight movement upstream of the immobilized wires (towards the base unit) causes tons of blinking and great difficulty getting it to light again. I would almost be tempted to just attempt to immobilize the wires near the base except that the large range of motion demanded by the attached bridge would probably defeat any immobilization scheme and I'm not sure if there would be enough slack left over for normal operation and finally any small vibration would probably still break the sensor connection (probably with infuriatingly stupid timing) and really make me regret relying on that solution. So, I'm thinking I need to open the case, inspect the cable connections for obvious opportunities to fix and if nothing can be done there, close up the patient note time of death and print up my RMA labels.