Can't change out wireless router that is connected to switch

[thepuregamer]

Awhile back, my house was wired with ethernet by a IT technician but I desire to change the arrangement and haven't been able to get a hold of him. He set up my wireless router directly connected with the cable modem in the basement and the wireless router has an ethernet cable going to the 16 port switch. Sadly, I now realize that putting the wireless router in the basement seriously reduces the coverage of the house with wireless. I wanted to directly connect the modem to the 16 port switch by just directly connecting the ethernet cord from the modem into the switch in the same port that it was connected to the wireless router, but when I do this, I lose internet connectivity in all the ethernet ports that were set up around the house. So directly connecting doesn't seem to work. I bought a cheap ethernet router/switch to take up the position of the wireless router in this setup but that also doesn't seem to work. What steps should I take to troubleshoot this problem?

My hardware is listed below:
Netgear ProSafe 16 port gigabit switch gs116
N600 Wireless Dual band router ( takes in ethernet from modem and has a ethernet cable going to the 16 port switch)
Arris TM822 cable modem
Linsys SE1500 5 port switch (wanted to basically swap cables connected to wireless router and place them connected to this so I can place the wireless router upstairs where it should cover my whole house.)

Thanks for the help.

Update: Photos of my setup can be found in my drive

 

[bill001g]

You would need 2 cable to the room upstairs. You go one cable from the modem to the router on the wan and then a second cable from the lan back down to the switch to run the rest of the house.

If that is not a option then you need to get a AP which can be another router just setup to run as a AP.

What you do is leave the router where it is and just plug the AP into the jack upstairs. It would go from your router to the switch to the AP.

 

[thepuregamer]

You would need 2 cable to the room upstairs. You go one cable from the modem to the router on the wan and then a second cable from the lan back down to the switch to run the rest of the house.

If that is not a option then you need to get a AP which can be another router just setup to run as a AP.

What you do is leave the router where it is and just plug the AP into the jack upstairs. It would go from your router to the switch to the AP.

I have attached photos of my setup to my original post. Looking at the setup, would I still need an access point upstairs?

 

[bill001g]

No way to tell it depends if 2 of those jacks go to the room you want to put the router in. It does look like there are using jacks for phone you might be able to use them both for data.

 

[tman1]

Power cycle the cable modem after connecting it to the new router.

 

[thepuregamer]

Power cycle the cable modem after connecting it to the new router.

Will try that and let you know if that works.