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PCM, ECM & BCM clarification

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Old Jan 19, 2013 | 11:49 AM
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Default PCM, ECM & BCM clarification

I have a few questions hopefully a few people can chime in and help me out
1. PCM is 24x and ECM is 58x?
2. Does a 04 GTO 5.7 come with a ECM or PCM
3. I have a 98 block so I take it I have a 24x reluctor wheel what does a 04 5.7 have 58x or 24x??

The reason I ask these questions is because I have a GTO gauge cluster I want to use with my swap but after doing some research I found that the Gen III PCM cant communicate with the BCM, that I would need a GenIV so the GM High speed LAN network can work together with a BCM that feeds the cluster?
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Old Jan 19, 2013 | 03:38 PM
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PCM -Powertrain Control Module
it Controls Both the Engine and the Transmission all in one unit

ECM - Engine Control Module
It only controls the Engine, No transmission Controls built in
it typically sends messages thru the CAN bus to a separate Transmission Control Unit(TCU)

BCM - Body Control Module
this typically is responsible for things like Lights/Security/Power Windows/Power Locks/sometimes radio and GPS integrated functions/ETC....

the 04 GTO comes with a 24x crank reluctor wheel and has a PCM that is responsible for both engine and Transmission Control

if you wish to use the 04 GTO Cluster, you will need the PCM and BCM from an 04 GTO
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Old Jan 21, 2013 | 01:18 AM
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Thanks for the response. So the 04 PCM will work with my 98 block?
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Old Jan 21, 2013 | 02:27 AM
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Originally Posted by mdrn69velle
Thanks for the response. So the 04 PCM will work with my 98 block?
the block itself does not matter as long as you have the correct sensors that the PCM is looking for.
which If I recall correctly, I think it was all the same on the engine..
might have some issues with the Fuel Sender and some other miscellaneous things...but nothing that would keep the engine from running as far as I can think of
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Old Jan 21, 2013 | 10:17 AM
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Originally Posted by mdrn69velle
Thanks for the response. So the 04 PCM will work with my 98 block?
It will work on the block, but the harness you choose needs to match the computer. Same with the injector connectors, coolant temp sensor, ect...
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Old Jan 23, 2013 | 09:42 PM
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Yea found out the A/C, fans and injectors, coolant temp just to list a few was the main thing & other misc stuff was changed on the harness... When I said block I really meant that if they have the same reluctor wheel on the crank (98/04 blocks). Sorry didn't explain that in detail.
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Old Feb 7, 2013 | 12:27 AM
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TTT
Originally Posted by mdrn69velle
Yea found out the A/C, fans and injectors, coolant temp just to list a few was the main thing & other misc stuff was changed on the harness... When I said block I really meant that if they have the same reluctor wheel on the crank (98/04 blocks) . Sorry didn't explain that in detail.
Trying to get a solid answer before I buy the PCM.
Wich I believe is It is Service Number 12586243 Hardware Number 12583659
Green and blue caps on harness??
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Old Feb 7, 2013 | 08:59 AM
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My post number 5 answered your question already.
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