SLS inactv got me stumped

[GSXRliterbikz]

So, Thought I had the issue licked a while back. But I'll start fro the beginning.
01 x5 4.4 sport with rear axle air.
First got the warning almost a year ago.
Scanned it with inpa, and had a right rear sensor voltage implausible code.
Bought a new one from the dealer and installed it.
No change. Same code.
Looked over the wires, nothing stuck out as bad.
I had a spare module, so I swapped it in and the ride height came up and I thought it was fine. But the inactive warning was still on the dash.
Scanned it again and no had the same code for the left rear sensor.
Happened to have a spare one from a parts car so I swapped it in for testing purposes.
No more issues. No warning, codes, all was right with the sls world.
Fast forward 6 months. Bing, sls inactiv pops up again. Codes for the right rear sensor again. This time, since I noticed the sensors are the same, I swapped them. Code stayed the same. Right rear.
I no longer have a spare module to play with.
I tried testing voltage on the wires. Unplugging the module, and testing the yellow/grey wire on the harness, the right sensor has low voltage. .01/02 fluctuating. Sometimes higher if I load the suspension. Left sensor is .07/08 and slightly higher for loaded readings. I'm assuming the issue is the module sees different values and doesnt like it, then turns on the warning.
But I cant seem to find the cause.
The piviot arms are fine. I greased them up to make sure they move freely. The right sensor is new oe (now its on the left side). Module is different (not new, but from a working X). Bags hold air for a long time. Pump comes on when triggered with inpa.
I'm a bit stumped. Not even sure what else I can test/replace.
Any ideas?