Immediate help needed. Checksum failed: $0548

Hey guys. I've been going back and forth with Les from Silver Bullet Tuning about tuning my dad's '06 Megacab. Well, initially, it was tuned with a Smarty Jr. Due to that, the ECM was "locked" and wouldn't allow a reading. As suggested by Les, we tried a full flash with a stock tune that he sent me. That was unsuccessful. We then tried another tune from Tune File Depot. Same results. We tried flashing both tunes more than once.

We are now stuck with a disabled vehicle and need it in 2 days! The V2's bootblock and firmware are up-to-date according to the control panel as well as the latest V7.5 and V8 software. Shortly after, Les brought it to my attention that the files need to be in the ".ctz" format rather than ".ctd." The file that Les sent me was a ".ctd" and I opened it in the with the V7.5 Tune Tool and saved it as a ".ctz" and the other I got from Tune File Depot is in the ".ctz" format. Neither of those tunes flashed and resulted in the same "Checksum failed" error.

Please, HELP!

It sounds to me like your ecm is bricked. Other than having a dealer attempt a reflash I don't know what else to do than tell you to replace the ecm. I have a new ecm that I can ship out on monday, you'll have it tuesday. If you're interested text me @ 7l7-44O-82O7
Sorry I can't offer more help!

What does Les think?

Sh!t. Figures, first attempt and the ECM bombs.

I haven't heard back from Les yet.

For the benefit of everyone who comes across this thread, I'll cross reference it to the thread on our forum

Immediate help needed. Checksum failed: $0548

Cheers
Cindy

Thanks, Cindy. I spoke with Donna earlier today if you didn't know that already. Excellent support! Thank you and everyone else so far!