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In hex 9C 40 00 00 or 00 9C 40 00 not sure on this placement of zeroes
But this is 160,000 kms exactly!

I programmed it using sps and I inputted the exact km as 160000

It sent that value repeated 3 times.

I can read the current mileage via mode 3B

But want to know how it’s. Calculated divide by 16, then covert to
Hex didn’t work

multiply the hex by 4 I believe.. I don't think it's always the same for every bcm though..

this a cruze?

160000 kms to hex = 27100 ÷ 4 = 9C40 yup!

ironduke wrote:multiply the hex by 4 I believe.. I don't think it's always the same for every bcm though..

this a cruze?

It’s a trax 2015

Same program should work for 2018
Colorado but it’s value is
33 4E 14

Which I think it had like 52340 kms or something like that ?

Also e78 pcm 2017 Silverado kms 82,xxx roughly
Is not repeated 3 times
Just ounce it’s 00 57 E0 1D

04colyZQ8 wrote:

ironduke wrote:multiply the hex by 4 I believe.. I don't think it's always the same for every bcm though..

this a cruze?

It’s a trax 2015

Same program should work for 2018
Colorado but it’s value is
33 4E 14

Which I think it had like 52340 kms or something like that ?

Also e78 pcm 2017 Silverado kms 82,xxx roughly
Is not repeated 3 times
Just ounce it’s 00 57 E0 1D

Ok 334E X 4 = CD38 in hex which is 52536
Plus 14 x 4 is 50 hex which is 80 total 52616 kms that’s prob correct or close enough

I don’t think that quite works maybe the last bit is 10ths of a km? Or something like that

I can’t seem to get the millage to change the type 4 app works I have a log of it and send the same commands
Unlock 27 01
Send 27 02 key
Get key excepted response
Then 3x x 01 01 00 00 I forgot the front part but this I think is
Service mode request? Possibly telling the size of the next message?
Then 3B xx (millage repeated x 3)

But when I do it with elm327 I get correct unlock response
But after I send 3B xx (millage repeated x 3)
I get 6 41 7B 31 error

Maybe the cluster needs to be on board? The type 4 app only works in the vehicle .

I also wanted to try this on a pcm e78 stored kms as well I can read it via
1A xx on the pcm likely it can be programmed as well I get postive I lock message as well
But same 7e8 7B 31 error back. Perhaps this one fails for incorrect programming message

3x x 01 01 00 00 Because I think this tells the length or size and the pcm has a smaller
Millage length it’s only 8 bytes think like xx xx xx xx.
If I knew what the 01 01 00 00 means I could adjust it.

04colyZQ8 wrote:I can’t seem to get the millage to change the type 4 app works I have a log of it and send the same commands
Unlock 27 01
Send 27 02 key
Get key excepted response
Then 3x x 01 01 00 00 I forgot the front part but this I think is
Service mode request? Possibly telling the size of the next message?
Then 3B xx (millage repeated x 3)

But when I do it with elm327 I get correct unlock response
But after I send 3B xx (millage repeated x 3)
I get 6 41 7B 31 error

Maybe the cluster needs to be on board? The type 4 app only works in the vehicle .

I also wanted to try this on a pcm e78 stored kms as well I can read it via
1A xx on the pcm likely it can be programmed as well I get postive I lock message as well
But same 7e8 7B 31 error back. Perhaps this one fails for incorrect programming message

3x x 01 01 00 00 Because I think this tells the length or size and the pcm has a smaller
Millage length it’s only 8 bytes think like xx xx xx xx.
If I knew what the 01 01 00 00 means I could adjust it.

Quick check I use to see if it's a formatting error or if I'm just locked out from writing something with a 3b command is to try and write what's already there.. Mileage I think is 99 so do a 1a 99 read and then try writing back what you read.. If that write test is successful then it's not the formatting or write command failing when you try to change it but your locked out from changing for another reason.
Not sure just how to unlock it in that case. maybe changing enable counter from 00 to something else?

I've seen the ECM odometer DID as $DF. It's 4 bytes long and E=N/64km

gmtech825 wrote:I've seen the ECM odometer DID as $DF. It's 4 bytes long and E=N/64km

Yes it’s DF to write as well but not working maybe I need to send enable 03 programming and quite
All modules first but that doesn’t seem to be working using the elm 327