Visa Required if transit less than 24 hours and stay within airport terminals ?

I am travelling to China for a holiday with my wife but now have to make a trip to Malaysia from Beijing for 3 weeks urgently. So I plan to extend my flight departure from Beijing to Seattle by about 3 weeks and take a separate flight from Beijing to Kuala Lumpur and back. On my return (I am a Malaysian with a green card) to Beijing to fly out on the same day, is a visa required if I am just collecting my bags at Beijing and checking into the next flight to Seattle? I assume I will need to go through border control to collect my bags which are from a different airlines. I have to go from terminal 3 to terminal 2 to check in bags and board flight back to Seattle. Thanks