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GAMEOVER
April 19th, 2009, 04:30 PM
The last 3 trucks that I've worked on, the speedo-calculator has kicked my butt...:nixweiss:
The speedo fine tuning doesn't apply the changes when I plug in the values into the Displayed speed and actual speed. It shows the corrected value needed but doesn't show the new VSS pulses per mile or Km.

When I measure the roll out of the tire(circumference) and put in the values, the speedo calculator is usually right but...When a combination of bigger/taller tires and lower gear ratio's are used it's hit or miss...:(

I can usually get to within +/- 2mph but the ABS and Brake lights always stay on...

SUPERTRUCKER
April 19th, 2009, 04:39 PM
The last 3 trucks that I've worked on, the speedo-calculator has kicked my butt...:nixweiss:
The speedo fine tuning doesn't apply the changes when I plug in the values into the Displayed speed and actual speed. It shows the corrected value needed but doesn't show the new VSS pulses per mile or Km.

When I measure the roll out of the tire(circumference) and put in the values, the speedo calculator is usually right but...When a combination of bigger/taller tires and lower gear ratio's are used it's hit or miss...:(

I can usually get to within +/- 2mph but the ABS and Brake lights stay on...

Are you using a GPS to get the actual speed to apply the corrected value?

GAMEOVER
April 19th, 2009, 05:31 PM
Yes always....

GAMEOVER
April 20th, 2009, 12:34 PM
Worked on a different truck today, 2008 Silverado 1500 4WD 5.3ltr (E38) 4L70E(T42) I tried to adjust for taller tire's & new gear ratio size....No Go!
35" tall tire & 4.88 rear gears....:nixweiss:

GAMEOVER
April 20th, 2009, 05:06 PM
Do I need to make changes to {H0122}?

EFI Live won't let me make changes to {H0101}
After It shows me the "Correction Value Required" I click on the apply button and nothing happens...I then try to add the correction manually to {H0101} but the software won't let me....

GAMEOVER
April 21st, 2009, 02:20 AM
Anyone got any Ideas???????????:help2::help2::help2:

Blacky
April 21st, 2009, 08:19 AM
The speedo calculator is not capable of calculating speedo setups for ALL GM vehicles. There are so many ways of setting up the speedo that it is virtually impossible to automate the process the same way across all PCMs. For non LS1/LS2 and Diesel vehicles I recommend not using the speedo calculator and just adjusting the speedo parameters* manually.

*i.e. manually figure out and change the tire size and gear ratios in both the ECM and TCM.

Regards
Paul

GAMEOVER
April 21st, 2009, 09:31 AM
Paul,
Do you think I'm having problems because I've never changed the parameters in H0122?
I can figure out the tire size and where to adjust them but new gear ratio's and where to apply them(?????) is what's kicking my butt...

GAMEOVER
April 21st, 2009, 09:40 AM
:doh2::doh2::doh2:
I feel really DUMB!!!
I just figured out the parameters in the TCM!!!
Thanks Paul, I'm glad you mentioned the TCM...Or else I would have never figured it out...:D:D:D

Blacky
April 21st, 2009, 11:14 AM
Paul,
Do you think I'm having problems because I've never changed the parameters in H0122?
I can figure out the tire size and where to adjust them but new gear ratio's and where to apply them(?????) is what's kicking my butt...

Yes, H0122 is the diff ratio.
Paul

Blacky
April 21st, 2009, 11:17 AM
:doh2::doh2::doh2:
I feel really DUMB!!!
I just figured out the parameters in the TCM!!!
Thanks Paul, I'm glad you mentioned the TCM...Or else I would have never figured it out...:D:D:D

One thing to note, I am fairly confident that changing H0105 will adjust the needle in the dashboard without affecting the speed registered in the ECM. So if you scan SAE.VSS and you see 60mph, and you are actually traveling at 60mph (as verified by some external source i.e. gps) but your speedo needle
shows 90mph, then adjust H0105 to alter just the needle position.

Let me know how you go with setting up the speedo.
Any feedback will help me improve speedo configs in future.

Regards
Paul

FTK_Ray
April 30th, 2009, 04:54 AM
I am having a similar issue. when I change for tire size manually it corrects the speedo but intermittently at startup there is no light but when the truck is put into reverse it sets brake and abs light? If you dont go into reverse it never sets the light or if you go back to stock tire size then the lights never come on at all but the speedo is off?

Maxwell Power
April 3rd, 2014, 10:32 AM
I am having a similar issue. when I change for tire size manually it corrects the speedo but intermittently at startup there is no light but when the truck is put into reverse it sets brake and abs light? If you dont go into reverse it never sets the light or if you go back to stock tire size then the lights never come on at all but the speedo is off?

I know it's a resurection.

Does H0137 fix that?