Replacing a electric receptacle in the middle of a series
This example should trip the breaker the second it is turned on.
Someone screwed up and stabbed the reds on the wrong side. They probably broke the tab to get half the receptacle to work and not trip the breaker, or pulled the red feeder at the switch.
When the new receptacle is installed don’t use the backstabs--they are the leading cause of failure. Pigtail is the correct method, or use more expensive outlets which have a plate at the screw and allow 2 wires per screw.
The tab should be broken on the black/red or &quot;hot&quot; side. The tab should not be broken on the white side.
Normally the red is a switched hot and the black is a always hot. Since this was mis-wired it would never work with both receptacles.