BlueRacer

Prior to disconnecting the battery, should you put the stock tune back in prior to disconnecting the battery? Or does it not matter? Bought a new battery, figured I better be sure before I disconnect the battery.

grss429

I'd do it just to be safe, but i dont think it matters as it's stored in the PCM

vintageman

I have disconnected my battery with the Level 2 Tow loaded and it is still good afterwards. Don't think it will be an issue.

Mod (Ret.)

It's not an issue to disconnect a battery with a custom tune installed. As mentioned, it's stored in the PCM, so it acts just like the factory tune would. Since we'd do nothing different with a factory tune when changing the battery, no need to do anything different with a custom tune.

Kevinpmac

Had battery changed with custom MPT tune installed with no issues at all

techrep

iTrader: (1)

No Need to....

BlueRacer

Thanks for the info. Much appreciated

techrep

iTrader: (1)

Yep...

LEN671

I had a custom tune installed, but when I was changing it back to the stock tune, something happened and now when you insert the key and turn it to the "ON" position, or the position before actually starting the vehicle, it will just keep cranking, but not start or turn over. Any help or advice will be greatly appreciated and welcomed. Thank you in advance.

LEN671

it also doesn't stop "cranking" until I remove the key completely.