bdphourde wrote:
I am having trouble performing the firmware reset for my 2020 Mac Mini M1. I had to get another M1 computer just to be able to perform the reset. I ordered the DFU cabable USB-C cable needed. I went through the special procedures for start up, but results were the same as a regular boot try. The screen remains dark and the SIL is still continuously amber. How do I check to ensure I have the right cable? And why are there two different USB-C cables with no way of telling them apart by markings? Why would they make one the passes power but no data, and one that passes data but no power, and not give as way to tell the difference beforehand? As I only have one monitor, I have to use it for the working computer for the check. So I have no screen indications to verify, but it isn't booting, so I don't really need a monitor.
The "broken" Mac which you are trying to put into DFU Mode will not give you any visual indicators. The only possible indicators will be macOS booting normally, or perhaps the Caps Lock key will light up when pressed which usually indicates the Mac has booted (hard to say how far it may have booted without a screen).
The most information you will receive during the DFU Revive/Restore process will be shown in the Apple Configurator app.....that information will be very limited to "DFU Mode", no information indicating powered off, or a screen indicating it is powered on. You need to use the latest version of the Apple Configurator app version 2.19 which requires macOS 15.7.5+ Sequoia or macOS 26.x Tahoe on the host Mac. Using any older version of macOS on the host Mac (or any older version of Apple Configurator or even using the Finder on Sequoia) will result in failure (personal experience). In fact, using the wrong OS on the host Mac when using the Finder will result in the "Revive/Restore" button not even activating & providing no error message even when the "broken" Mac is in DFU Mode, with the proper USB-C port & USB-C cable (USB protocol only).
I never liked DFU Mode on iPhones or iPads, and I despise DFU Mode even more on the Macs.
As for USB-C type cables....they are a complete mess & are very confusing even for techs. When you buy a cable, you need to know exactly what you are buying....making sure to remember what that cable is. The good USB-C cables will clearly denote the protocols supported by providing designation for the USB protocol being used, or the Thunderbolt protocol supported.
The Apple branded USB-C charging cables purchased direct from Apple will include absolutely no markings. These cables only support the very slow USB-2 protocol and allow for charging devices. It is a shame Apple helps create even more confusion with the USB-C cables by not marking them properly.
Generally a Thunderbolt cable will have a lightning bolt on the connector and may have a number indicating the version of the Thunderbolt protocol supported, or a speed rating.
With a USB only cable, the marking symbols can vary greatly. Older cables may have a trident like symbol, while newer cables may have a modified symbol along with "USB" on it, or it may just show an image of a cable with some numbers. Generally if there are any numbers, it will indicate the maximum supported transfer rate.
USB-C charging cables may have a marking indicating a charing or power symbol (various kinds). Some USB-C charging cables may only support charging & may not support any data transfer protocols. Or some, like the Apple USB-C charging cable may support USB data transfers at a transfer rate of USB2 (40MB/s...very very slow).
Except for the Apple USB-C charging cables which are actually of good quality (poor identification), people should avoid unmarked USB-C cables because if a manufacturer cannot be bothered to identify the cable, then the quality of the cable is probably very poor.
