I got an ethernet run put in the walls recently, 2x cables from and to double faceplates. One of these runs has been fine since install, but I (foolishly) didn’t test both immediately after install. One of these runs works as expected at full gigabit. The other will only negotiate to 10 Mbps.
Now here is the kicker - I put a nail into the wall a good 20cm away from where I thought the ethernet would be (vertical run) before trying to use it and finding out it only does 10. Anyone know how likely it is I could have nailed a cable and dropped it to 10 through damage, or is it more likely to be a bad install? Electrician claims they both tested the same at install but hasn’t been back to check anything yet. Could a nail drop it to 10 without fully breaking the connection? Or is it more likely to be a bad crimp or mixed pairs?
An ethernet cable tester is kind of cheap. When I fitted my gigabit wiring it ran at 10mbit and the cable tester showed 1 of the 8 pins was not disconnected. It is full steam ahead now. Like this: https://www.screwfix.com/p/philex-network-cable-tester/93219
It just lights up the lights representing the 8 wires, in order. Watch closely and I do believe one of the 8 will not be connected somewhere.