Write fail no start

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Somewhat new to tuning done 20-25 tunes and have had issues with connections on hummers so I use a bench rig for them but had a 03 suburban 1500 I am messing with did first couple write no problem then recalibrated the mass air and during the write it made it to 92% and stopped. Ended up timing out and now ecm wont respond and no start. Hooked up a spare ecm I had sitting and will spin over on that one. Vehicle never dropped power or connection. It the ecm trash and now have to pay for new ecm and dealer programming so I can start all over? Is there a way to reset the original or?

[EWY]

I have never had an issue with it not writing fully but I have had an issue having to reset the PCM after every write. Have you tried to reconnect it after installing the other PCM?

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*Fixed issue

First thing I want to correct it when I say no start I mean vehicle wouldn't even engage the starter.

I replaced the exm with a known good one and after theft learn could start vehicle. Replaced old ecm and still wouldn't turn over.

I was able to fix the ecm by bringing it home to my bench learn rig I made. On bench rig I was able to connect to the ecm and do a rewrite to save the ecm. It is back in the vehicle running. I assume with the write being incomplete the computer locked itself from the vehicle but my bench setup doesn't have anything but obd port, power and grounds so no modules to fight.

[EWY]

Great! I am glad you figured it out. I have been meaning to make a bench harness myself. I just never get myself to sit down and do it.