2.Unscrew 3 screws (step 1), unscrew 5 screws (step2 & step 3) (shown in the yellow square), unplug 17 connectors (XHD4)/ 16 connectors (HD4) (shown in red circle) to remove Main Board Module.
XHD4 Model:
Step 1
Step 2 & Step 3
HD4 Model:
Step 1
Step 2 & Step 3
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