tcm, bcm, ecm ?

Hey, Your question is to vague.. TCM = transmission control module. BCM = body control module. ECM = Electronic control module ( a generic term for all of the control modules). The output speed sensor is used by the TCM and PCM (powertrain) to calculate vehicle speed. What is the specific concern????

modtop71 said:

Hey, Your question is to vague.. TCM = transmission control module. BCM = body control module. ECM = Electronic control module ( a generic term for all of the control modules). The output speed sensor is used by the TCM and PCM (powertrain) to calculate vehicle speed. What is the specific concern????

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ECM= Engine control module.
What I am asking is what these computers do, specifically. you know, like the BCM (Body control Module) Controls the interior lights, power windows, Seats, etc. Specific lists like that. I asked about the output sensor, to see if it had any other purpose then the speedo.
My specific concern???
Well, I'm trying to diagnose a problem, buy elimination, But need to know the possible electronics involved in the problem In order to eliminate them. My problem is listed in the forum here, and no one seems to know the answer.
I am quite convinced that my problem is electronic, and not a physical prob. with the trans. What I really want to know, is what electronics have anything at all to do with shifting, that could keep the car in limp mode.