Changed Transmission Input Speed Sensor, still get same error.

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JohnInSeattle

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Yes, I am not used to having spinning magnets around.
If The issue was caused by moving magnets. I would expect it to either get worse with speed, since the EMF generated by a moving magnetic field is proportional to it's speed or to have certain speeds where it resonates and be reproducible by speed.
Neither of these is true, so I feel I can safely eliminate magnetically generated EMF as the cause of the issue.
Still need to graph the solenoid currents. There are two that are right next to the sensor wire Looks like N91 and N731
 
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Jack@European_Parts

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okay........how about air gap of sensor or the reluctor fitment offset?

If The issue was caused by moving magnets. I would expect it to either get worse with speed, since the EMF generated by a moving magnetic field is proportional to it's speed or to have certain speeds where it resonates and be reproducible by speed.
Neither of these is true, so I feel I can safely eliminate magnetically generated EMF as the cause of the issue.
Still need to graph the solenoid currents. There are two that are right next to the sensor wire Looks like N91 and N731

I said 'reluctor' not moving magnet.

example.....

In ignition system. The reluctor ring is mounted on the crankshaft so that as the crankshaft rotates the magnetic sensor is triggered by notches in the reluctor ring. The magnetic sensor provides position information to the electronic control module, which governs ignition timing.
 
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JohnInSeattle

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There is a reluctor and a magnetic ring ( I can tell by the metal dust stuck to it)
The reluctor is formed by the edge of the clutch housing, and that OBVIOUSLY won't cause any EMF.
The Magnetic ring is back by the oil pump, I carefully cleaned off the metallic dust.
The bigger news is, Changed the Mechatronic unit and the problem is gone.
No more error codes. works good.
The more I think about the errors, the more I am thinking the TCM was having issues.
By the delayed and missing readings, It was getting stuck on some part of it's program loop and not able to take readings in a timely fashion.
If this was one of the normal controllers I program, I would hang a logic analyzer on it or put debug messages in the code to find the issue.
On this one, Obviously I don't have that kind of access through the VAGCOM, and am stuck just changing out the whole darn thing.
 
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