At least that is the way I understand it.
Difference between ECM and PCM
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Drifting
Joined: Aug 2007
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From: Homer Glen IL
Difference between ECM and PCM
Tuner recommended a new ECM for my 00'. I notice on the internet the Acronyms are used interchangeably. Which is which are were are they located on the car?
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Melting Slicks
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From: Iowa
ecm I think usually stands for electronic control module. PCM stands for powertrain control module. they are the same thing! and in days where there are more than one computer in a car, PCM makes way more sense. I'm pretty sure that's what the service manual calls it.
when I hear ecm or ecu to describe the PCM I think of cars from the era when they would have special badging that says fuel injection.
when I hear ecm or ecu to describe the PCM I think of cars from the era when they would have special badging that says fuel injection.
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From: Columbia SC
My C5 Factory Service Manual (FSM) uses the term ECM and PCM to refer to the same device. Mostly it is called PCM in the FSM, but in some locations it refers to the PCM as a ECM.
It (PCM) is located below the battery, not a great idea but that is where it is located. Good reason to monitor your battery for leakage. If you ever charge your battery in the car, be careful not to overcharge it or you can get acid on the PCM and/or connectors (2) which is a bad thing. Most people here use a trickle charger to keep the battery charged if the car is not driven regularly. I prefer to use a Battery Minder, but there are many others. These are smart chargers and are designed to not overcharge the battery.
Your tuner needs to explain why he wants it replaced and let us know to see if we agree.
It (PCM) is located below the battery, not a great idea but that is where it is located. Good reason to monitor your battery for leakage. If you ever charge your battery in the car, be careful not to overcharge it or you can get acid on the PCM and/or connectors (2) which is a bad thing. Most people here use a trickle charger to keep the battery charged if the car is not driven regularly. I prefer to use a Battery Minder, but there are many others. These are smart chargers and are designed to not overcharge the battery.
Your tuner needs to explain why he wants it replaced and let us know to see if we agree.
Burning Brakes
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From: South Riding VA
Just to add some details: when gm changed to the electronically controlled 4l60e transmission in the c4 ( think it was around 94) they added those control functions to ECM. Because it now controlled the transmission as well as engine functions they changed the name to The Powertrain Control Module (PCM).
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From: Orlando FL
Just to add some details: when gm changed to the electronically controlled 4l60e transmission in the c4 ( think it was around 94) they added those control functions to ECM. Because it now controlled the transmission as well as engine functions they changed the name to The Powertrain Control Module (PCM).
cool