How is gm bcm millage calculated?

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04colyZQ8
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Re: How is gm bcm millage calculated?

Post by 04colyZQ8 »

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

That’s cool but I don’t think that’s write? The otter way seems correct as mentioned earlier
Convert to hex divide by 4. 64 doesn’t seem to work
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Gatecrasher
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Re: How is gm bcm millage calculated?

Post by Gatecrasher »

DID value is standardized. EEPROM value can be module specific. It gets translated when you read and write the DID.
04colyZQ8
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Re: How is gm bcm millage calculated?

Post by 04colyZQ8 »

Oh ok so far the read 1A DF equals the eeprom on both bcm and pcm exactly:)
ironduke
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Re: How is gm bcm millage calculated?

Post by ironduke »

Not trying to Hijack but this topic made me curious about the 07-13 IPC's in the trucks since that's where the odo is stored on these..
Very easy to read and just about as easy to change. Doesn't even have a seed/key.
Vin was very easy as well..
They really should have made it a little harder.
04colyZQ8
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Re: How is gm bcm millage calculated?

Post by 04colyZQ8 »

ironduke wrote:Not trying to Hijack but this topic made me curious about the 07-13 IPC's in the trucks since that's where the odo is stored on these..
Very easy to read and just about as easy to change. Doesn't even have a seed/key.
Vin was very easy as well..
They really should have made it a little harder.
Crazy! I have tried to read the colorado 04-12 ipc they all hace seed 555, tried no key cannot unlock with anything!

I have been unable to change the millage without dps, not sure why unlock ok, and thinkI'm send correct commands! Very surprised E78 stores kms too was trying to change it as it has 0 new! kms and the truck it's going into has 56,000kms not sure it matters but would be nice to get it to go!

Beware of this.. I tried the dps archive for millage on it and before that it was a unlocked controller with MEC at 255, and when-it got down to 250 I reset it to 255. however during the type 4 millage app run it sets mec to zero!! now its locked and reporting seed and key, and will not go back to 255! So that sucks! MEC is now perminately zero.
ironduke
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Re: How is gm bcm millage calculated?

Post by ironduke »

04colyZQ8 wrote:
ironduke wrote:Not trying to Hijack but this topic made me curious about the 07-13 IPC's in the trucks since that's where the odo is stored on these..
Very easy to read and just about as easy to change. Doesn't even have a seed/key.
Vin was very easy as well..
They really should have made it a little harder.
Crazy! I have tried to read the colorado 04-12 ipc they all hace seed 555, tried no key cannot unlock with anything!

I have been unable to change the millage without dps, not sure why unlock ok, and thinkI'm send correct commands! Very surprised E78 stores kms too was trying to change it as it has 0 new! kms and the truck it's going into has 56,000kms not sure it matters but would be nice to get it to go!

Beware of this.. I tried the dps archive for millage on it and before that it was a unlocked controller with MEC at 255, and when-it got down to 250 I reset it to 255. however during the type 4 millage app run it sets mec to zero!! now its locked and reporting seed and key, and will not go back to 255! So that sucks! MEC is now perminately zero.
So the Colorado IPC has a seed of 0x0555 but you've tried brute forcing it and no key works?? What's the response when trying to unlock it? Any idea what the delay has to be in between attempts?? Most ecm's are 10 seconds in between attempts..

I haven't really messed with odometer in anything except for the very recent attempt with the 2007-2013 silverado's I just did so I am very green, lol.. Oh and the 03-06 ipc's in the trucks too, but there's IPC hammer for that..

I've tried to change the MEC myself on a few modules and never got it to change, Is there a valid response if you send it a 27 03 request?? Might be able to unlock the 2nd level and then change the MEC? Any chance you saved the log of the type 4 routine?
04colyZQ8
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Re: How is gm bcm millage calculated?

Post by 04colyZQ8 »

I have a log of the mec reset i think..
It’s not type 4. Just started standard bin file
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