Reports are coming in that a fixed version of the raspberry pi 4 in the 4GB version has started to come through via distributors and this has been confirmed by the raspberry pi foundation. While some people have encountered this version as far back as november they are now becoming more comonplace. The new version fixes the CC resistor issue with the first revision. The backpowering issue is reported to not be fixed however the workarounds discussed previously should still work on the new revision. Getting the new version does not yet apear to be a certanty, as the one I got recently was still the original version.
Visually the new version looks nearly identical to the original version with no silkscreen or major component changes. On the bottom there is a relocated three pin component now next to the micro SD card test (the sd card power switch) which isnt there on the original version. You can also check th board revision in software, to check the version you have you can run “cat proc/cpuinfo | grep version”. The original version with the issue is “c03111” and the fixed version is “c03112” for the 4GB ram version I would expect the one and two GB ram versions to follow the same pattern when they start to appear.
While I have been unable to confirm as the schematics for the new revision have not been published yet. Looking at photos of the new version board posted online it appearas as though the original Rd pulldown resistor has not been changed being on the same place as before and no new components appear to have been added so I am unsure as to where the new resistors have been placed. I will update this post when I find out more info on the implementation.
updates
* 2020/03/24: Updated section on new CC circuit due to incorect guess on purpose of SD card voltage switch
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