Troubleshooting Game Card Reader Error

I was intermittently getting errors reading game cards but it was mostly working.

Unrelated to the game card reader error I broke a joystick and replaced both joysticks myself. The joystick repair seemed to go fine and is working after the repair, but of course I had to basically take apart everything to get to it. After being pleased that the joysticks work I realized that the game card reader no longer works at all (no game cards work in it).

I was thinking this is unrelated to my previous intermittent errors because it’s now happening on every card. And since I just took apart the entire switch I figured that I must have damaged the game card reader’s cable during my repair. I took it apart again and the I couldn’t find any apparent physical damage to the game card reader. I tried reseating the cable but alas it still didn’t work with any game cards..

I thought maybe I couldn’t see the damage to the game card reader so I ordered a new game card reader, installed it, but I am still seeing the error on every card. I tried reseating the cable on the new game card reader to be sure, but it did not help.

Is there anything else to do?

I suppose it’s possible that the replacement game card reader is defective but how could I know for sure? Is there any way to determine if the replacement game card reader is defective or if the issue is elsewhere?

Do you think I damaged it in the repair or do you think it’s related to the original intermittent card reader errors I was seeing before the joystick repair? But more to the point, how can I troubleshoot this? If it’s not the game card reader, could it be anything else besides the motherboard? I assume if it’s the motherboard then the switch is basically not repairable as I don’t even see replacement motherboards really available, right?

Any ideas? Thanks.