V1 Resetting the Odometer - How To

[Chubbs]

EUREKA! I figured it out.

The issue is the 3.3 volts the CH341a programmer puts out. It's not enough. I reworked the CH341 programmer to output 5v to the chip, and it read right off the board. No need to desolder the chip at all. Just clip on and it reads. The voltage rework is here:

next issue was with TachoSoft. The version I downloaded (free, and probably pirated) did not have a 2007 Cobalt. only 2004-2005, and then another for 2006. However, you'll notice there is a pattern. on lines 3B0 and 3C0, there are some characters that repeat 3 times. All the other cobalts listed the same characters, so I just assumed 2007 was the same, and it was. Tachosoft was in kilometers, so I had to do that calc to miles, and it spit out a set of hexdata to change.

My car now has 5367 miles on it, which is a 5000 mile motor when I bought the car (new long block), plus the miles I've put on it since the build. It's approximate, but it's much closer than the 136k miles it showed before.

 

[Ross]

Wow! Good work, that is an important discovery! I'm going to have to try this again.

 

[Keckster]

EUREKA! I figured it out.

The issue is the 3.3 volts the CH341a programmer puts out. It's not enough. I reworked the CH341 programmer to output 5v to the chip, and it read right off the board. No need to desolder the chip at all. Just clip on and it reads. The voltage rework is here:

perfect! I tried doing the 5 volt mod but ended up breaking programmer and haven’t tried since. Thanks for doing the extra research and checking if that was the issue!

 

[Romeo]

Thanks for sharing I have this all setup and working

 

[Cnixon160]

Anyone ever unintentionally add a bunch of features to the cluster menu while resetting their mileage? I somehow managed to add all of the power lock, tpms, remote start, and keyless entry options to by 2010 XFE base model BCM, I saved both BIN files and the only change is the four bits in the three locations being zeros but I have much more listed now

 

[NextFungus]

Anyone ever unintentionally add a bunch of features to the cluster menu while resetting their mileage? I somehow managed to add all of the power lock, tpms, remote start, and keyless entry options to by 2010 XFE base model BCM, I saved both BIN files and the only change is the four bits in the three locations being zeros but I have much more listed now

Do you have a way to verify you didn't already have the options?

 

[newbtrying]

I'm a Montana resident and I've installed a 0 mile F23 trans and fully rebuilt my 2.0 LSJ, so it's basically a 0 mile car. I'd like to reset the odometer to reflect the ~10 miles i've driven it since it's conception but i'm not sure the legality in my state, or even how to figure that out. I'm looking into insuring and registering the car currently, but have not done that yet. Is the odometer reset something i must do before registration?

Assuming I am able to and do reset the odometer to reflect the current miles on the car, I'm definitely not going to DIY. I'll send to Odo Pro. I'll call them Monday to see if they can help answer any of these questions if none of you experts know off the top of your head.

 

[CaptFrank2001]

ODO Pro did mine. https://odo-pro.com/

 

[comegetjoe]

I and I know others along with CaptFrank have used odopro.

 

[newbtrying]

I and I know others along with CaptFrank have used odopro.

Did you guys have to disclose to the government that you changed the odometer?

 

[Keckster]

Did you guys have to disclose to the government that you changed the odometer?

I changed the mileage before I registered the car. I imagine changing the mileage after initial titling would be an issue

 

[comegetjoe]

I changed the mileage before I registered the car. I imagine changing the mileage after initial titling would be an issue

This.

 

[Markm]

I also used odo pro. I sent it in and had it set to zero when building the car. Check with your state on odometer requirements. Tn has a statement for mileage if you change it.

 

[Robinjo]

I and I know others along with CaptFrank have used odopro.

I did too, super easy to deal with.