Mac Pro 2006 not seeing drives in internal bay

[jt_69.V]

Hello, I have several Mac Pro 2006 and one of them suddenly cannot see any drive in its four internal bays. When I insert a drive in any of these bays, The Mac shows the blinking folder with question mark icon on boot. I checked that the drive (SSD) does have a valid system on it and can boot another Mac Pro 1,1.
Any idea on what happened and what I can do to keep using this old Mac Pro ? Thanks...

 

[jt_69.V]

Nobody ?

 

[hwojtek]

Boot it off USB and look into SATA section of System Information. Perhaps you'll find a damaged SATA controller in there.

Or just check if the SFF-8087 plug connecting the controller to the backplane sits correctly in the socket (under the drive cage #4 - unplug using the latch lever, plug again, check booting).

 

[jt_69.V]

Boot it off USB and look into SATA section of System Information. Perhaps you'll find a damaged SATA controller in there.

Or just check if the SFF-8087 plug connecting the controller to the backplane sits correctly in the socket (under the drive cage #4 - unplug using the latch lever, plug again, check booting).

A thousand thanks, it worked perfectly ! I just unplugged and plugged back the connector and now the Mac sees the internal drives again. Although it looked well in place that was enough to make it work again. Thanks !