I went to flash my ecu using up tuners and it keeps failing during the write procedure. My battery is only 6 mos old and my fuse is good. Someone please help me. Symptoms I have when writing is the gauges go all the way down then back to normal levels like the truck is shutting itself off. Any ideas? I'd hate to have to walk 20 miles to get home

 

Is the cable plugged in all the way... I hada similar situation with mine where it would just fail to write...

 

What year and ecm?

 

Yes cables all plugged in. 06 Yukon Denali and stock ecu

 

Are you doing a Write or Write entire?

 

While it tries to write the volt meter goes all the way to zero. Kinda like a key off during write.

 

Battery terminals tight and good contact?

 

Yes and I'm just doing a write Calibration

 

Vehicle won't start now either because it erases the previous Calibration. Tried writing the stock file I saved and still no dice. It only write to 10 percent and then fails for timeout. Tried to use slow speed as well I stead of high speed and same result

 

Do you have a remote start in your truck?