If You Have Ever Purchased an E38 ECM and Overwritten It, Please Read This
01-28-2012, 01:31 PM
#1
Staging Lane
Thread Starter
If You Have Ever Purchased an E38 ECM and Overwritten It, Please Read This I am interested in buying a used (already programmed by GM) E38 ECM for my 2012 Corvette. I know that I need to buy a part number (SERV #) 12633238 from a 2010-2012. I keep getting conflicting and/or incomplete advice (even from HP Tuners "tech support") whether ANY 12633238 can be overwritten with an HP Tuners .hpt file using "Write Entire"; or whether only Corvette ECMs will work (not from trucks like Sierra or Escalade) or whether I can only overwrite certain operating systems. (?)
Does anybody have any real world experience with this - not just hearsay, or "I think..."? Has anyone actually purchased a used ECM and written a tune from a newer version using Write Entire? Has anyone ever bought an E38 from a 2010-2011 truck or van and overwritten a Corvette tune to it? Although a $100 used ECM is not expensive, it's wasted money if I just lock it up trying to program it.
Thank you for your time.
Does anybody have any real world experience with this - not just hearsay, or "I think..."? Has anyone actually purchased a used ECM and written a tune from a newer version using Write Entire? Has anyone ever bought an E38 from a 2010-2011 truck or van and overwritten a Corvette tune to it? Although a $100 used ECM is not expensive, it's wasted money if I just lock it up trying to program it.
Thank you for your time.
01-29-2012, 04:00 PM
#4
Staging Lane
Thread Starter
Hey you guys,
Thank you for taking time to respond.
What I am told by an HP Tuners employee is that the "operating systems" are changed almost quarterly, and this is the 8-digit number which is at the top of the ECM label. Nobody as of yet has mentioned "Slave Operating System".
The slave operating system must be different from the operating system if one person is telling me they change every three months and another is saying it is the same in most newer contollers. Could you elaborate on what exactly the slave operating system is vs the operating system? Is this the TIS and SPS programming done at the dealer? If so, is the slave operating system different on a truck vs a car?
The challenge here is that I am not a GM dealer, and all the local GM dealers I have called can not program an ECM without the car being present; and it's difficult to get the car to the dealer with a non-functional ECM. So I'm trying to buy an ECM which I can simply write over. Have either of you ever taken an E38 ECM from a sierra or escalade or other truck and just written a Corvette tune to it using the "write entire" function on HP Tuners?
Thank you
Thank you for taking time to respond.
What I am told by an HP Tuners employee is that the "operating systems" are changed almost quarterly, and this is the 8-digit number which is at the top of the ECM label. Nobody as of yet has mentioned "Slave Operating System".
The slave operating system must be different from the operating system if one person is telling me they change every three months and another is saying it is the same in most newer contollers. Could you elaborate on what exactly the slave operating system is vs the operating system? Is this the TIS and SPS programming done at the dealer? If so, is the slave operating system different on a truck vs a car?
The challenge here is that I am not a GM dealer, and all the local GM dealers I have called can not program an ECM without the car being present; and it's difficult to get the car to the dealer with a non-functional ECM. So I'm trying to buy an ECM which I can simply write over. Have either of you ever taken an E38 ECM from a sierra or escalade or other truck and just written a Corvette tune to it using the "write entire" function on HP Tuners?
Thank you
01-30-2012, 10:27 AM
#5
Just get it flashed initially with a tech 2 and you should be fine AS LONG AS THE SERV NUMBER MATCHES your original unit.
The slave os is the low lying operating system kind of like a bios is to a home computer. It needs a slave to work. HOWEVER the operating system and the slave have to be compatible. If not, the unit will die. As the pointing registers will point to the wrong spot in the os and cause it to lock up in a loop that is not possible to get out of, Well unless you cut it open and BDM it, but the end user would not be able to do this cost effectively...
Just keep this simple.
If you have to get a replacement ecm, Get one with the same SERV number, and get it flashed with a tech2 or mdi box FIRST, then you should be good. Throttle will work, and no issues with non compatibility.
A hint also on compatibility, 2006-2008 should be ok, 2009 to 2010 should be ok, 2011-2012 should be ok.
The slave os is the low lying operating system kind of like a bios is to a home computer. It needs a slave to work. HOWEVER the operating system and the slave have to be compatible. If not, the unit will die. As the pointing registers will point to the wrong spot in the os and cause it to lock up in a loop that is not possible to get out of, Well unless you cut it open and BDM it, but the end user would not be able to do this cost effectively...
Just keep this simple.
If you have to get a replacement ecm, Get one with the same SERV number, and get it flashed with a tech2 or mdi box FIRST, then you should be good. Throttle will work, and no issues with non compatibility.
A hint also on compatibility, 2006-2008 should be ok, 2009 to 2010 should be ok, 2011-2012 should be ok.
