I was tuning a friends LB7 truck and wanted to upgrade to DSP 5. Something happened during the tune, it did not finish and the chip in the ECM fried. I got the communication error code, the fast blinking of the injector relay in the truck and no start. I sent the computer out to SoCal Diesel and they verified the chip was fried and replaced it for me. EFILive kindly replaced my VIN Licence and I had my buddies truck going within a week. I installed a tow tune with the new licence and all was good.

Since then I bought a bench harness for my tuning, and I've successfully tuned a few LB7 trucks to DSP5 with the bench harness. No problems at all.

This weekend I went to tune my friends truck to DSP5 (the one with the repaired ECM). I put it on the bench harness and tuned it and it finished successfully. Went to start the truck and the same thing happened! Went to read the ECM with EFILive and it said there was loss of communication. No start.

I'm lucky my friend has a second vehicle so he can afford the inconvenience of having his truck not running while I try to get this figured out. I'm at a complete loss as to why this is happening, and it's getting expensive. Any help would be greatly appreciated. I love the EFILive tuning software but at this rate I won't be able to afford it.

Thanks in advance.