Bootloader rejected

[limited cv8r]

Having trouble flashing and reading PCM in a commodore. Keep getting a bootloader rejected or no response from PCM with V7 & V8. Scan tool will connect and work, HP Tuner will read from PCM, any suggestions. Could a bad USB connection cause this?

[joecar]

Which PCM...?

Which V7/V8 build versions...?

[limited cv8r]

Gen iii , ls1b. Originally tried with whatever version was installed. Updated to RC3 and latest firmware. Still the same.

[limited cv8r]

Small update on this. Ended up using Roadrunner to tune vehicle. Could bench flash PCM no problem and eventually worked out could read and write to PCM with high speed unchecked. Maybe just a problem vehicle, something to remember for the future.

[Supercharged111]

Is this a 1MB LS1b PCM? I have all kinds of issues with those in the trucks. I basically get one shot and if I fail, take a 5 minute spin shut down and try again. Repeat as necessary. Really sucks when you have to burn the license and then tune. It took a while to come up with that. Another way is there's a data fuse under the hood you can pull, but a drive around the block seems to work best for me. It's the bus that pisses it off so bad, or rather everything on it.

[limited cv8r]

512mb PCM , never really had this much trouble before. At least its done and out of my hair now :beer:

[GMPX]

Rarely hear of comms issues on LS1 cars these days, must have been something with the car itself.