test 5 =1.76v but if I disconnect the the transmission connectors it is 5v. unsure if I was supposed to reconnect after test 4.
Yes, it's not clear, but for test 6 it says connect all, so presumably in 5 the transmission is not connected yet. The 5 V is as specified. There's no spec for the voltage on pin 6 with the tranny connected so no idea if the 1.76V is correct.
However, I'm wondering if that drop to 1.76 V could be a factor. In test 5, the 5 V must be coming from the TCM. The other two terminals are ground and the battery voltage, so this terminal must be the "signal". The sensor is probably a Hall Effect Sensor, with some circuitry built into the assembly in the transmission. When the turbine is rotating, the sensor circuit grounds the pin 6 line as the turbine magnet(s) pass the sensor. The effect is a square wave (as shown on your scope) that I would expect switches between zero and 5 V. When the transmission is connected but the engine isn't running, the Hall switching circuit should either be open (5 V on pin 6) or closed (zero on pin 6). The 1.76 V, therefore might indicate a problem in the sensor circuit that's loading the TCM input circuit. The effect is a square wave that can only go from zero to around 1.7 V (i.e. the 1.5 seen on the scope). That might be too low an amplitude (shift) for the TCM to accept as the turbine speed.
I wonder . . . with power off and the TCM disconnected (at B54 or at the B12/T3 junction), can you measure the resistance (Ohms) between T10 pin 1 and ground? This is measuring the Hall sensor output circuit. If it's low, that would explain the drop from 5 V to 1.76 V. My "Google research" on Hall effect sensors suggests that the output of the circuit, being a switch, should not have a low resistance.
This is only an attempt to explain the test measurements and the problem. Ideal would be to have the same measurements done at pin 6 for comparison. But perhaps step-by-step, we could narrow it down enough to suggest the right "corrective measure". (It might still come down to bad wiring connections at the sensor. If the wire bringing the battery voltage to the sensor at T14, pin 1, is bad, the actual voltage getting to the sensor circuit could be lower. -- more thinking on paper . . . )
Maybe we can find some data on the amplitude of the square wave signal . . .