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So I have a dodge intrepid the code reader says it's the ecm so I ordered the part but the one by the engine is a tcm one person says the tcm n pcm are the same thing but the ecm only has one connection while the tcm has 4 please help me out so I can get my car running again
 

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2002-2004 has a combined PCM/TCM. It's located behind the drivers side headlight.
 

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So I have a dodge intrepid the code reader says it's the ecm so I ordered the part but the one by the engine is a tcm one person says the tcm n pcm are the same thing but the ecm only has one connection while the tcm has 4 please help me out so I can get my car running again
To be clear:
For 1998 thru 2001, the TCM and PCM are separate. TCM has one connector, PCM has 2 connectors.

For 2002 thru 2004, the TCM and PCM were combined into one unit that is called the PCM. That one unit has 4 connectors.

In all cases, the terms PCM and ECM are used interchangeably.
 
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PCM and TCM are not the same things PCM is for the transmission while TCM/ECM is the computer control.
This info. is specific to the 2nd gen LH cars:

You are correct that the TCM and PCM are functionally not the same thing. But you have their functions reversed. The TCM is the electronics and firmware for control of the transmission, while the PCM/ECM controls the engine functions, plus a few other things peripheral to engine control (alternator output voltage regulation, fuel pump, radiator cooling fans, a.c., etc.).

From '98 thru 2001, they were two separate physical boxes. Starting in 2002, they were combined into one box that Chrysler calls the PCM. After 2001 we still at times may refer to the TCM, but it is understood to be the portion of the stuff in the "PCM" box that controls the transmission, and that in earlier years used to physically be in a separate box.
 

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This is info. is specific to the 2nd gen LH cars:

You are correct that the TCM and PCM are functionally not the same thing. But you have their functions reversed. The TCM is the electronics and firmware for control of the transmission, while the PCM/ECM controls the engine functions, plus a few other things peripheral to engine control (alternator output voltage regulation, fuel pump, radiator cooling fans, a.c., etc.).

From '98 thru 2001, they were two separate physical boxes. Starting in 2002, they were combined into one box that Chrysler calls the PCM. After 2001 we still at times may refer to the TCM, but it is understood to be the portion of the stuff in the "PCM" box that controls the transmission, and that in earlier years used to physically be in a separate box.
Out of curiosity, I just searched on the term "TCM" in different year 2nd gen FSMs, and I see that the later year ones sometimes refer to transmission control in the TCM, which is correct when/if understood in the context of functionality but it physically being in the PCM box. However, I see one illustration about removing the TCM that shows the pre-2002 TCM box that does not exist in those later years. That's either due to inadvertent oversight or conscious decision/"laziness" by whoever updated the FSMs (or their manager) not to put the time into fixing that.
 
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