hi 1337machine    Reference KB is Dell EMC Knowledge Article 000017840 : VNX2 arrays running Direct Current (DC) power who upgraded Block OE R33.102 or later will experience both Power Supplies as faulted and write cache will be disabled. There is Internal Notes in above KB and that is what you need to know , you need to find somebody can view this Internal Notes...(I hope you find the person can help you ) 
Hoping someone can help. I have a VNX5200 that has been retired from production and is slated to be used in a lab environment. I'm trying to get the firmware updated, but I can't because there are fault statuses indicating that both PSUs are faulted and unrecognized: [IMAGE] The unit is no longer covered under a maintenance contract, and is not going to be. I came across the following community post indicating that there's a good chance that this is a known code issue as per Dell - Solved: Bus 0 Enclosure 0 faulted - Dell Community The VNX unit is running 05.33.009.5.155 Since the only solution is to contact support, I gave it a try hoping that they would work with me to resolve it since it's a known issue, and the only solution is to contact them. As I'm sure you all can imagine, they refused. So, I'm left to my own devices on this one, it seems. I've spent about a week searching every corner of the internet for a solution. I've tried literally everything I can find. No amount of reseating PSUs and SPs, naviseccli syntax, rebooting SPA, SPB and CIMOMs is clearing the fault statuses. If support can fix this, that means that there's a way to do it. I do have the engineering passwords for Unisphere and USM, but I haven't been able to locate anything that can help fix this. Ultimately, I'm thinking there has to be some sort of method to clear the fault statuses and update the firmware, force the firmware update even though there are fault statuses, or change the "rules" so that USM doesn't check for faults... or maybe some naviseccli magic that I just haven't figured out.  naviseccli -h sc_off - doesn't fix it either.  I was hoping that there might be some sort of factory reset capability, or a maintenance NDU, but no luck there either. I know the answer has to be out there somewhere! I'm hoping someone can help! Please and thank you!
VNX5200 - Bus 0 Enclosure 0 is faulted 0x7402