When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
DOES ANYONE KNOW WHAT CONTROLS THE ODOMETER ON A 91 VETTE---IS IT CONTROLED IN THE COMPUTER OR IN THE DASH DISPLAY?
IF YOU PURCHASE A NEW DASH PANEL--DOES GM LOG YOUR MILAGE WHEN YOU PURCHASE IT?? THANKS IN ADVANCE
JIMBO
:jester
DOES ANYONE KNOW WHAT CONTROLS THE ODOMETER ON A 91 VETTE---IS IT CONTROLED IN THE COMPUTER OR IN THE DASH DISPLAY?
IF YOU PURCHASE A NEW DASH PANEL--DOES GM LOG YOUR MILAGE WHEN YOU PURCHASE IT?? THANKS IN ADVANCE
JIMBO
:jester
The Central Control Module (CCM) (I think the '91 has one, I know it was in the '92) keeps track of the odometer reading. The CCM is behind the radio in the dash.
GM makes it difficult to modify the readings in the CCM for obvious reasons.
As long as you use the old CCM, the odometer readings remain the same.
If you change the CCM, there is more than the odometer that may be different. The CCM checks the ignition key resistance and passes the information on to the ECM. It also has the option content of the vehicle, along with the VIN number. If someone decided to change the mileage by swapping the CCM from another vehicle, you can use a Vetronix Tech-1 or Tech-2 scan-tool to read the VIN number from the CCM and compare it with the VIN on the body -- if they are not the same, someone did a no-no.
As a P.S. here, if you need a new CCM, the Vetronix Tech-1 is capable of downloading the old readings out of the old CCM and uploading them into the new/Delco-refurbished CCM. Vetronix will supply the software to do this to a GM dealer or certified Delco shop. The idea is to prevent odometer tampering.
AS Scorp508 said, after the new/refurbished CCM is put in place, you only have about 100 miles to update it with the information -- after that, you are locked out.
Tom --thanks for the reply--my problem is my vette reads 169000 miles the ccm was taken out of a wrecked vette
my title reads 97000 miles--how do i get the odo. to read the title miles--can this be accomplished??--let me know if you can help--i do have a local shop that is certified. thanks jimbo :p:
Tom --thanks for the reply--my problem is my vette reads 169000 miles the ccm was taken out of a wrecked vette
my title reads 97000 miles--how do i get the odo. to read the title miles--can this be accomplished??--let me know if you can help--i do have a local shop that is certified. thanks jimbo :p:
Jimbo
The only way I know to accomplish this is to buy a new or delco refurbished unit and have a GM dealer or Delco shop set the values in the CCM before it reaches 100 miles. I have the same Vetronix Tech-1A that the GM dealers use, and Vetronix will not sell me the software to do this part. The dealer has what is called a "mass storage cartridge" that has the software to accomplish this. I borrowed the software from a friend at a dealer to do mine with my Tech-1A. Even a dealer can't change it after the 100 mile mark.
Be aware, you have to know all your options (like C68 climate control, ASR/ABS, etc) to program it in, along with your odometer mileage, VIN, etc.
This has been made difficult to do by design to prevent odometer tampering.
The only thing that I think you can change after the 100 mile mark is the ignition key pellet resistance reading.