Updated description by GoldenHelmet

Steps to reproduce

1. Load the attached test world, Detector rail inconsistency.mcworld
2. Press the button labelled "run test."

Expected result

Each detector rail detects the minecart coming onto it and powers the adjacent redstone lamp.

Actual result

Only the detector rails in the same chunk as the minecarts detect the minecarts and power the lamps.

Original description

The rail system is close to the same, but the detector rail is not being activated on one side (as indicated by one being lit up and the other not being). The system is around the same on both sides I repeat so I do not know what is the problem with this, but if one side seems to be working, why not the other? When it goes uphill, it stops there and the piston blocks it; however, the piston blocks it the same for both sides but does not activate the rail equally. If there needs to be more information on what I am building, I can provide the scenario but it is regrettable it does not work. Let me know if you can look into it. If you need to reproduce the problem, build an upwards track both aligned along the x-axis, and send one going upwards negative and the other positive, and the detector rail on the bottom (not to mention it is blocked with a fence or piston above the flat detector rail) will not activate one of the rails. To give an even better representation of this problem, I recreated the exact problem along the x & z-axis (can't do that y-axis because the game doesn't work like that).

While I was trying to fix the build of a system of Redstone, I found the exact direction of the railway to work apparently. However, I noticed the other railway built before still wasn't working. As I continued my quest for answers, I found this happening on the screenshot below that is the most recently added. Two identical railway systems pushed into the ends of them with only one turning on and the other still not on. I am more baffled at this.