2005 LS2 engine harness on a 2007 LS2 engine?
#21
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The 2007-2008 TBSS E67 ECM is part number 12636660.
Glad you asked this question because the ECM part number can make a difference. Some incompatibility problems exist between different software sets and ECM part numbers. You can turn an ECM into a paperweight if you put the wrong software into the wrong ECM. EFILive started checking for this (checking OS vs ECM model number) but you can sometimes still mess it up. I don't recall if the GM service software checks for this or not (they assume you have the correct part number for the vehicle you are working on). Not sure if HPTuners or any of the other aftermarket software checks.
So you would want to talk to who ever is going to program your ECM and make sure they plan to use a 2007-2008 Trailblazer SS software set or some other similar software set with the ECM. If it has the same OS (operating system) as the 2007-2008 Trailblazer then it should be able to be programmed into the ECM without any issues.
Here is a link to a document from EFILive that explains some of the compatible ECM and OS combinations.
Hope this helps (one less ECM paperweight and I have helped the world 8-) ).
Glad you asked this question because the ECM part number can make a difference. Some incompatibility problems exist between different software sets and ECM part numbers. You can turn an ECM into a paperweight if you put the wrong software into the wrong ECM. EFILive started checking for this (checking OS vs ECM model number) but you can sometimes still mess it up. I don't recall if the GM service software checks for this or not (they assume you have the correct part number for the vehicle you are working on). Not sure if HPTuners or any of the other aftermarket software checks.
So you would want to talk to who ever is going to program your ECM and make sure they plan to use a 2007-2008 Trailblazer SS software set or some other similar software set with the ECM. If it has the same OS (operating system) as the 2007-2008 Trailblazer then it should be able to be programmed into the ECM without any issues.
Here is a link to a document from EFILive that explains some of the compatible ECM and OS combinations.
Hope this helps (one less ECM paperweight and I have helped the world 8-) ).
Is there a part number on PCMs that I can determine if it is an E67 PCM. Are there other PCMs that would work on that harness?
I guess I should also ask, how do I verify that it is a correct harness if the year is not sure or unknown. Basically as just a secondary check to confirm the harness is correct.
thanks.
-Don
I guess I should also ask, how do I verify that it is a correct harness if the year is not sure or unknown. Basically as just a secondary check to confirm the harness is correct.
thanks.
-Don
Last edited by Jason Haines @ LPE; 02-11-2013 at 06:00 PM. Reason: Typo
#22
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Depends on the model year of the LS2 harness. I assume when you say LS3 ECM you mean an E38 (should be etched into the sheet metal backing plate on the ECM). I can't think of any LS3 applications that used any other ECM but I may have forgotten something.
A 2005 Corvette LS2 harness (E40 ECM) would NOT work with an LS3 (E38) ECM.
A 2006-2007 Corvette LS2 harness (E38 ECM) would work with an LS3 (E38) ECM.
A 2005-2006 SSR LS2 harness (E40 ECM) would NOT work with a LS3 (E38) ECM.
A 2007-2009 Trailblazer SS LS2 harness (E67 ECM) would NOT work with a LS3 (E38) ECM.
A 2006-2007 CTSV LS2 harness (E67 ECM) would NOT work with a LS3 (E38) ECM.
A 2005-2006 Pontiac GTO harness (E40 ECM) would NOT work with a LS3 (E38) ECM.
So from what I typed above the answer is that most LS2 harnesses won't work with an LS3 ECM.
Depending on what combination you end up using (harness, ECM and software set), some harnesses may have a different connector for the MAP sensor, MAF sensor, injectors etc. Make sure who ever calibrates the ECM knows what MAP and MAF sensor you have (they have different calibration curves) along with which injectors you have etc.
BTW - not very important but in GM speak an LS3 has an ECM (Engine Control Module). The 1997-2004 Corvette had a PCM (Powertrain Control Module). The difference being that the PCM controls the transmission and the engine.
A 2005 Corvette LS2 harness (E40 ECM) would NOT work with an LS3 (E38) ECM.
A 2006-2007 Corvette LS2 harness (E38 ECM) would work with an LS3 (E38) ECM.
A 2005-2006 SSR LS2 harness (E40 ECM) would NOT work with a LS3 (E38) ECM.
A 2007-2009 Trailblazer SS LS2 harness (E67 ECM) would NOT work with a LS3 (E38) ECM.
A 2006-2007 CTSV LS2 harness (E67 ECM) would NOT work with a LS3 (E38) ECM.
A 2005-2006 Pontiac GTO harness (E40 ECM) would NOT work with a LS3 (E38) ECM.
So from what I typed above the answer is that most LS2 harnesses won't work with an LS3 ECM.
Depending on what combination you end up using (harness, ECM and software set), some harnesses may have a different connector for the MAP sensor, MAF sensor, injectors etc. Make sure who ever calibrates the ECM knows what MAP and MAF sensor you have (they have different calibration curves) along with which injectors you have etc.
BTW - not very important but in GM speak an LS3 has an ECM (Engine Control Module). The 1997-2004 Corvette had a PCM (Powertrain Control Module). The difference being that the PCM controls the transmission and the engine.
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thankks for the info. It's been extremely helpful. I have a pcm with a number at the top of the sticker that says 1261863 and I can't seem to find it on that efi list.