When writing with HP Tuners, do you guys use the write calibration only or do you write entire? Dumb question but I couldn't find the answer anywhere. I just started tuning via HP Tuners last night and even though I'm an amateur tuning diesels we've already knocked off half a second in 0-60 via GTech (for what its worth).

You just do a write cal only, you can't do a write entire on a LBZ any way ;)

Only time you should need to do a write entire is when changing operating system (custom OS's and such). Cal's will do any tunning you should need :)

As stated above write calibration only is the write of choice.

More info can be found in the Writing the vcm (http://www.hptuners.com/help/vcm_editor_flash_menu_write.htm) portion of our help file.

Thanks guys...I was curious because on my friends trailblazer ss you have to write entire

Thanks guys...I was curious because on my friends trailblazer ss you have to write entire

Yeah the E67's require a write entire, as do fords, all others a write calibration only should be the norm.

Thanks guys for answering that but a new question has formed. When I go to load a new tune on different days...lets say I load one on the 10th and see how it does and load a new one on the 12th....on the 12th, I have to always read the tune first before I can load the new tune. Why is this?

Im not sure I understand your question, you don't need to read the pcm to do a write, to perform a write just open the file you want to write & click the write calibration icon to start the process.

Ok, maybe the wording is a little confusing. I understand I don't need to read before I write a calibration. However, on different days that I tune, I HAVE to read the truck first before it will allow me to write a calibration. I get an error message saying that the OS is not valid.

Ok, maybe the wording is a little confusing. I understand I don't need to read before I write a calibration. However, on different days that I tune, I HAVE to read the truck first before it will allow me to write a calibration. I get an error message saying that the OS is not valid.

I have the same issue. Also on a 06 LBZ.

I have the same issue. Also on a 06 LBZ.


Did you guys read a different vehicle before trying to write to another vehicle?

No I am only working on mine right now.

Please contact support with a vcm suite infolog while connected to your vehicle and the file your having problems with and I'll look into it.

Ok...I'll make a post on hptuners.com and I'll see what I can give you...thanks! Give me a few days...its my brother's truck and he won't be back from his honeymoon until Sunday.

Did you guys read a different vehicle before trying to write to another vehicle?
Nope, I read the vehicle...made changes....loaded the tune. Next day after a little driving, tried to load another tune (same truck...just different day/time) and wouldn't do it...I had to read the file first.

Nope, I read the vehicle...made changes....loaded the tune. Next day after a little driving, tried to load another tune (same truck...just different day/time) and wouldn't do it...I had to read the file first.

Realize you cannot just load a random tune, it MUST be the same operating system/vcm id number that came from the truck originally.

Realize you cannot just load a random tune, it MUST be the same operating system/vcm id number that came from the truck originally.

I uploaded and saved ( because it would not let me download a modified previous upload) then I could download. A few days later I wanted to download the before mentioned upload and it would not let me without uploading again first.
It says the operating system does not match or something like that... When I get a chance I will replicate it and get the error.

This is all with the same truck and computer

I uploaded and saved ( because it would not let me download a modified previous upload) then I could download. A few days later I wanted to download the before mentioned upload and it would not let me without uploading again first.
It says the operating system does not match or something like that... When I get a chance I will replicate it and get the error.

This is all with the same truck and computer

Yes please and send a detailed description ie
Opened xx.hpt file
Clicking write calibration only
xx error came up on screen(attached screenshot)

or whatever it is that happened as the way you stated it is very confusing & honestly I don't understand what your saying. Theres NO reason our software would not allow you to read(your term download) ANY file off of ANY pcm we currently support.

Realize you cannot just load a random tune, it MUST be the same operating system/vcm id number that came from the truck originally.
I understand that but I am not loading random tunes. I am loading tunes based on the stock file which has been modified by me. In other words, OS 12375403 and VIN 1G48038575043G9308 (for example) is what I am working with, and I am loading modified tunes from the stock tune for this same VIN and OS. And it sends a message, Invalid OS. Please check your VIN. Or something like that, and the only way I can tune is to read the file that is in the computer(title it delete) and load my modified tune that I already made.

Does that make better sense?

I have never had that happen to me, but hp's tech support are pretty helpful I'm sure they'll take care of you, bill helped me out when my truck wouldnt start or except a tune when an eror occuerd during a write, word to the wise when modfying a tune in a parking lot, although rare it is possible to get stranded :)

Yes please and send a detailed description ie
Opened xx.hpt file
Clicking write calibration only
xx error came up on screen(attached screenshot)

or whatever it is that happened as the way you stated it is very confusing & honestly I don't understand what your saying. Theres NO reason our software would not allow you to read(your term download) ANY file off of ANY pcm we currently support.

Are you Bill?

Read from PCM = upload
write to PCM = download

I READ and saved ( because it would not let me WRITE a modified previous READ) then I could WRITE. A few days later I wanted to WRITE the before mentioned READ and it would not let me without READING again first.
It says the operating system does not match or something like that... When I get a chance I will replicate it and get the error.

This is all with the same truck and computer

I understand that but I am not loading random tunes. I am loading tunes based on the stock file which has been modified by me. In other words, OS 12375403 and VIN 1G48038575043G9308 (for example) is what I am working with, and I am loading modified tunes from the stock tune for this same VIN and OS. And it sends a message, Invalid OS. Please check your VIN. Or something like that, and the only way I can tune is to read the file that is in the computer(title it delete) and load my modified tune that I already made.

Does that make better sense?

Weird, contact support.

Are you Bill?

Read from PCM = upload
write to PCM = download

I READ and saved ( because it would not let me WRITE a modified previous READ) then I could WRITE. A few days later I wanted to WRITE the before mentioned READ and it would not let me without READING again first.
It says the operating system does not match or something like that... When I get a chance I will replicate it and get the error.

This is all with the same truck and computer

weird, contact support as well, never seen this happen before.