I just found this. It seems to be what you're looking for. In short, yes. There is a difference. Do you need that feature? I have no clue.
"Anything is possible with an internal problem.
Clear the codes and see what comes back.
If it keeps repeating, it suggest that any attempt to read inductive signitures will generate a code even if there is no problem with the part.
The chip that does this will fail everytime it is supposed to read a signiture.
You may even get away with it causing no drivability issues until a 'real' fault with say a trans shift solenoid occurs, then you may not be able to ID the trouble due to the faulty chip .
Then you have two problems.
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To expand on this, the PCM uses this chip to tell if......
1. an action has occured ok.
2. was it to slow?
3. is the winding shorted?
4. is the winding open?
5. is the operation stuck etc
6. any external issue in the harness such as a short to ground or a cross to battery.
It does all these things by analysis of the operational signiture expected for the part and action requested.
The device is at a 'chip level' because it's composed of a lot of circuits that do different things as mentioned above and report to them to the main PCM program via a 'bus'.
The 1636 says that 'bus' is open.
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A more simple example is the power window operation as monitored by the GEM. The motor hardware has no up or down stop switches so how does it know when to stop powering the motor? Ans, by the increase in current when the window is fully either up or down against travel limits, the GEM reacts instantly to a rise in current draw of the motor and opens the relay.
This is in part to keep children from getting their heads/neck/hands etc caught when fooling around with the window closing switches and backed up by a driver cut- off switch on the arm rest when there is a chance of an incedent.
I can't stress enough how much computer control there is and how many owners are unaware of that level and think things are so much simpler than it really is."