Chromebook 7310, weak signal

I had the exact same issue, spoke with several repair shops.  Oddly, the signal got weaker the more the lid was opened.  Seems as if the antenna is getting pinched by the lid opening.  Not worth the cost of repair.  

I think this is a common problem.  The antena wire goes over the hinge and breaks after a while. The wire runs from the WiFi card (by the tab key), under the motherboard to the other side and over the hinge by the power button. When it breaks, the length of the wire under the mother board acts as a weak antena.  My signal would improve when I partially closed the lid...probably brought the break together.

Simple fix ( I won't get into details) is to replace a couple of inches of antena wire that goes over the hinge. It isn't going to break anywhere else. If you are getting a weak signal, the WiFi card is OK.

A shop could do this easily in under a half hour. Just shop supplies, no parts, so should be inexpensive....or do yourself if handy.

get your antenna changed it would help to fix up your problem

1. First make sure that the signal is not weak due to the network and router (try with a mobile phone)
2. Uninstall the original wireless network card driver, left click "This Computer" and select "Properties".
Click "Device Manager" and click "Network Adapter" to find the wireless network card.
Right-click "Uninstall", check the uninstall driver and click "OK" to download the wireless network card driver and install it.

The previous comment makes no sense. There is no device manager in Chrome OS, and there are no drivers and no there is no way to uninstall or install drivers on Chromebooks.