I mac mid 2010 21.5" Model A1311 (4SNS/1/c0000008: TG0H- -124) error

[jo498]

I have a I mac mid 2010 21.5" Model A1311 3.06 mhz I ran a hardware test and got an error code 4SNS/1/c0000008: TG0H- -124 . I think it's the GPU sensor . And my screen is black, no back light but i have it connected to a tv and it works. Does anybody know error code meaning ?

 

[AdamCRHall]

A little late but for future reference -

I had this exact code: this may be caused by the MXM sensor plugged into the back of the board behind the WiFi card and the bit connected to the Graphics card heatsink.

I suspect yours is cause by the graphic card failing though.

I upgraded from an i5 to an i7, the ODD fan was at max speed afterwards. I spent ages purchasing a new ODD sensor, replacement fan, OWC ssd thermal sensor cable kit, etc to see if any of those were the issue and I had no luck.

After reinspecting, it turns out I’d either forgotten to plug the MXM sensor back onto the board or had knocked it out somehow.


This resolved my issue and I hope this helps anyone in the future.