Troubleshooting: Why the normally closed and normally open pin in my relay is shorted internally?

Another possibility is that you have misidentified the pins.

Bob

 

Another is if the relay has been used and the N.O. has welded to the common, this then shorts all three contacts.
M.
edit: make that N.O.

 

The N.O and N.C. contacts are normally physically separated by an air-gap with the movable common contact in between. To have continuity between a pair of N.O. and N.C. contacts requires that both the N.O. contact and the N.C. contact be "welded" to the common contact across the air gap! That condition is likely to be fairly obvious upon inspection of the relay, and there is probably no way to "fix" it. However, I suspect you are not measuring what you think you are measuring. Try measuring again with another relay of the same type and report back here with the results. Also, a model number and a pin-out of the suspect relay would help us identify what appears to be wrong. Show us these and explain which pins you are using to measure continuity between.

 

Care to clue us in?

Bob

 

If in doubt, read the instructions!
M.

 

Always read and understand the datasheet for every component in a project before proceeding. From discussion on another thread you started, may we assume the diagram below represents the relay you are trying to use?