No Crank, No Start After Recent SCT Tune

Hi everyone, and I appreciate your time and assistance in advance.

I recently loaded a new tune onto my 2007 GT using an SCT 4 tuner. The vehicle ran great for the day after making the adjustment; however, now it is the next day and my vehicle wont crank. I am getting these DTC's when attempting to start my vehicle:

P0600

P1000

P2105

U0300

I am loosely aware of what these codes mean individually, but I am looking for some guidance on more specifically what the cause could be and potentially what I can do to solve my issue. So far I have tried to remap the vehicle onto a stock tune with no avail and it still throws the same codes. This is my daily driver so any assistance would be greatly appreciated. Thank you!

99% of the time it is the battery that has gone bad. Replace it and you are golden. The codes are meaningless when the computer is getting low voltage.

Those codes wont keep it from cranking.
Check battery volts.
Starter may have taken.a dump.

Oh interesting. Okay, I appreciate it. I'll update everyone tomorrow.

Those are common communications errors that occur when the voltage are too low while loading a tune. Another possibility is that you have selected an incompatible tune, and it halted during loading.

Put a charger on the battery, return to the stock tune, then try again once you’ve got it running again. It’s best to ALWAYS connect a charger before/during the loading of a tune.

crjackson2134 said:

Those are common communications errors that occur when the voltage are too low while loading a tune. Another possibility is that you have selected an incompatible tune, and it halted during loading.

Put a charger on the battery, return to the stock tune, then try again once you’ve got it running again. It’s best to ALWAYS connect a charger before/during the loading of a tune.

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^^^This^^^

I have had a similar thing happen on my car would not crank at all and my sct tuner would not connect to the pcm and i could not clear the U0300. Tried everything in regards to the battery and charging but that made no difference. Finally i disconnected the battery for 10 min or so and went straight into return to stock that worked so once that was completed i reloaded the tune i was using and everything was back to normal. Strange but if you are still having this issue try the return to stock but do it straight away after you reconnect the battery cos i had tried it once before after i had been trying to clear the fault codes and then it would not do anything.

I think I found the issue. I recently updated the x4 tuner and now its stating it is no longer married to my vehicle. So, I am assuming my stock tune was lost and is what's causing the issue. SCT won't answer my calls or respond to my support ticket. Any suggestions?

Update should not have unmarried the x4.
Did you try to load your custom tune?

Juice said:

Update should not have unmarried the x4.
Did you try to load your custom tune?

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Initially I attempted to, but then tried to upload the stock tune.

Oliver Vigil said:

Initially I attempted to, but then tried to upload the stock tune.

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You mean "restore to stock" by "loading stock tune"?
If yes, then that is what "unmarried" the device. Did the flash finish without error?

So, what happens when you try to load your custom tune now?

SCT device update is never a good idea unless SCT tells you to do it. Most of the update is canned tunes for ALL supported vehiclesby SCT.

Juice said:

You mean "restore to stock" by "loading stock tune"?
If yes, then that is what "unmarried" the device. Did the flash finish without error?

So, what happens when you try to load your custom tune now?

SCT device update is never a good idea unless SCT tells you to do it. Most of the update is canned tunes for ALL supported vehiclesby SCT.

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The download did show that it completed. When I attempted to load my custom tune, it loads fine but no start. Loading stock or custom tune has same results. And ik... was the first time I did and I definitely fucked up.

Oliver Vigil said:

The download did show that it completed. When I attempted to load my custom tune, it loads fine but no start. Loading stock or custom tune has same results. And ik... was the first time I did and I definitely fucked up.

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Ok, now we are getting somewhere!
Since you state that the custom tune loads and completes, but the car will not start. That tells me the PCM is likely OK. If it was a bad flash, the X4 would report a communication error.

That brings me back to: it is likely not a tune issue. You do not get an Immobilizer code, I dont think it is a PATS issue.

Can you jump the starter? Does it crank when jumpered?

Ill try to jump the starter, I assumed it wasn't an issue with the starter due to the codes being thrown. It could make sense though, ill give it a shot tomorrow and get back to you. If you have any other suggestions let me know. I REALLY appreciate the help.

So far, I dont think it is a PCM/tune issue.
Testing the starter will give us more info.

Just out of.curiosity, the theft light is not flashing after you turn the key to run, correct?

That was an error. Lol

Juice said:

So far, I dont think it is a PCM/tune issue.
Testing the starter will give us more info.

Just out of.curiosity, the theft light is not flashing after you turn the key to run, correct?

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Not sure, ill check when I get home today in a few hours. However, I have been having an issue with the alarm going off ever since the tune had issues. Wasn't sure if it was related.

Oliver Vigil said:

Not sure, ill check when I get home today in a few hours. However, I have been having an issue with the alarm going off ever since the tune had issues. Wasn't sure if it was related.

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This makes me think it has something to do with the PATS. If the car thinks it's being stolen it will disable the starter.

07 Boss said:

This makes me think it has something to do with the PATS. If the car thinks it's being stolen it will disable the starter.

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Hmmmm. Any ideas where to start to diagnose?

Did you check for power at the starter on the small terminal when cranking engine. Start with the basics.