some laptop keyboard keys not working after opening the laptop

hemdal

Commendable
Jun 25, 2016
10
0
1,510
i opened my dell inspiron 15r se laptop for fan cleaning after reassembling the laptop some keys are not working enter, backspace, p,o, r, t,v and b.
I typed this post using on screen keyboard.
I am going to open the keyboard again what might have gone wrong. what should i check.
 
Solution
Open it up again and clean the contacts of the cables with alcohol (isopropyl if possible or contact spray for electronics)
Reconnect and try again.

hemdal

Commendable
Jun 25, 2016
10
0
1,510
there are 2 cables on the keyboard one is big and other one is small its for the keyboard light both are attached.
Update: I again opened up the laptop cleaned off dust from the motherboard using cotton buds then reattached all the cables again and now space, backspace and enter and p buttons are working but keys b, t, r, v, g, arrow keys are not working. The external usb keyboard works fine.
Should i buy a new keyboard or did i damaged the motherboard