ST1000DM003 MCMainPORT Failed DWF Error Fix


This is one of success case done by DFL engineer in Korea yesterday. The user mentioned that the patient drive can spin up. But cannot get ID information, cannot back up sys file either. In the meanwhile, The terminal keep showing MCMainPORT failed error message.


Patient drive: ST1000DM003- 9YN162

PCB Number: 100664987

Capacity:1TB     FW: CC4B  

Reported symptoms

Cannot IDed, unable to backup SYS file, terminal error message keeps circulating.

Data Recovery Solution

Following steps were performed for this case:

  1. Managed to enter F3 T> once power on the program. Since MCMainPORT failed error message keeps circulating under terminal, it prevents the program to enter F3 T>. We have to press CTRL +Z to enter it once power applied.
  2. Tried to back up the important sys file via “Edit sys” function. Sometimes “Read sys” function may not work for some busy cases or IDed failed cases, then pls try to use “Edit sys” feature.
  3. Check G list and cleared G list by input related command.
  4. Check NG list.
  5. Initialize ID and un-tick Media cache.
  6. Regenerate translator. At this moment, we can see ID, no MCMainPORT failed error message again, but we are still unable to see module list and the DWF status was light on.
  7. Fix DWF common issue by just one click, then exit and re-enter the program.
  8. The whole drive can be scanned properly.

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