iMac Pro 2017" DFU Restore Error

[Stephen]

Did a major upgrade with OEM parts, now the iMac will not restore in DFU

here is the error message.

Unexpected device state 'DFU' expected 'Recovery' (Probably forced into DFU mode externally) [com.apple.MobileDevice.MobileRestore – 0xFAE (4014)]

Another message said something about communication with the device. I checked to see if there was fan spin and there is fan spin for 1 second then it stops and repeats. Any idea what is going on?

the iMac Pro has the T2 chip.

[Stephen]

Re: iMac Pro 2017" DFU Restore Error

Also went back in installed all the old parts and still wont recover. The iMac was working perfectly until the install. No parts were damaged. Wondering if the T2 chip on this went bad?

[Stephen]

Re: iMac Pro 2017" DFU Restore Error

I had a 2017 iMac had a similar issue where only one LED green light will turn on. It usually would be two before you hit power. So when I replaced the CMOS battery it turned on. This too also has a CMOS battery. However why would it die now after parts upgrade? Going to want suggestions, will replace the battery next to see if this solves the issue.

[Stephen]

Re: iMac Pro 2017" DFU Restore Error

well this is an odd battery for an iMac Pro 2017. It looks like a welded BR2450A Panasonic 3V battery but with two of them. Weird....

[Stephen]

Re: iMac Pro 2017" DFU Restore Error

Anyone have an idea where I can find this battery?

[Stephen]

Re: iMac Pro 2017" DFU Restore Error

Nevermind found the battery!

[Stephen]

Re: iMac Pro 2017" DFU Restore Error

Replaced battery same issue is happening. No clue. Only one Green light is on on the board.

[Stephen]

Re: iMac Pro 2017" DFU Restore Error

Visually the fans spin for one second and then stop and repeat. Nothing seems to be working. DFU wont post and nothing. Does anyone have an idea what ould be of this iMac Pro? Was working before the upgrade. Now just sol on the device and have no idea what to do next.

[smzlwan223]

Re: iMac Pro 2017" DFU Restore Error

Error 4014,1. It is like to know what parts you OEM, this is very important, second, whether you have removed the CPU cooling iron part, because removed, in the installation is very hot lead to the CPU pin deformation, or foreign body, not installed in place bending CPU. 2. Causing a 4014 error. I made some notes earlier. First, the hard disk part causes the hard disk part, such as the power supply, the hard disk and the T2 communication part, second, T2, detecting the voltage required for the T2 standby, third, the I2C bus part, fourth, the temperature control part. The best solution for you at present is to remove the motherboard, carefully check whether the motherboard is out of components, or components shift, whether the installation of wiring is not installed. I hope it will help you

[Stephen]

Re: iMac Pro 2017" DFU Restore Error

Thank you. I suppose maybe the CPU is the cause? So removing the CPU again and maybe trying this again.

[Stephen]

Re: iMac Pro 2017" DFU Restore Error

Update:
Still not working. Took the CPU out and cleaned it up tested it again no luck. Still getting the error. So decided to put back original CPU and still getting the same error and only getting one green light when I press the button to see the lights. Any help would be great.

[Stephen]

Re: iMac Pro 2017" DFU Restore Error

Read the ERROR and it appears the error is T2 RAM ERROR (4014) that we keep getting back. So put the original ram back in and now that is giving off an error as well (RAM ERROR) so maybe we should return this ram and order new ones from someone else? I though it was the CPU but it apprears according to T2 RESTORE on Wiki that error code is T2 RAM error.

[Stephen]

Re: iMac Pro 2017" DFU Restore Error

Ordered New Ram for this iMac Pro. Still giving RAM Error code for the T2. All we get is Quarter Fan spin. No lights on the board but one LED light when pressed. Can anyone point me in the right direction? Any suggestions would greatly help.