Factorio Forums

I was building a railway and two of my signals were flashing, switching between the three colors. Also one of my trains (I have two of them) was showing the "no path" symbol after stopping in one of the stations. I have no idea how to fix it so I would be extremely grateful if someone could help me. Here are the photos of my railway:

http://imgur.com/gallery/XT4WY

The last photo needs some caption:

-The big blue dots are the stations.
-The little pink dots are the signals.
-The blue arrows indicates the direction to which the trains are supposed to go.
-The gray triangles with an exclamation mark indicates the signals that don't work.
-One train goes from station 1 to station 3 and the aother goes from station 2 to station 3.
-The signal showing a yellow light in the first screenshot is one of the signals that don't work (I'm sorry I don't have a screenshot of the other one, maybe I'll post it later, but if someone could help me with this one it would already be awesome)

Matews12 wrote:I have no idea how to fix it

Keep reading for responses from other, but what I'll offer you is the method I used when I first started with trains. Break things down in small pieces when you're trying to find the problem. But first things first. I can't quite tell by looking at the pictures what you're using for signals. My advice for the signal is one that I've read multiple times. Always use chain signals (on both tracks) before the point where two tracks merge/cross, and use a regular signal after that intersection. Keep in mind that if you have tracks that go in both directions, you need to have signals on both sides of the rails, and the signals will be different from one side of the track to the next. For example, using R for a regular signal, and C for a chain signal, you would have something like this::
So if you follow all 3 paths, you can see that on the right hand side, the signals will be Chain signals before the merge point, but Regular after.

Once you get those sorted out, that should clean up your area a bit. The "No Path" is usually due to incorrect placement of signal. You need to ensure that you have proper signals between that train location to the destination, at every merge point at the very least.

This should get you started.

The no path likely means there is a single signal the wrong way on that route (trains wont go the wrong way through a signal unless there is also a signal exactly opposite). I normally find such issues by driving the train manually for a bit checking every signal i pass is on the right

If I'm not mistaking you are mixing sections of one-way tracks with sections of both-way tracks.
That can definitely work, but you will run into more problems with signals than when you would work with double tracks.

When looking at your drawing, from my perspective, there are quite a few signals missing.
For example the loop at the bottom right, with station 3. At the intersection, there should be a Chain-signal for the direction heading out of the loop ,
and a regular signal for the direction heading into the loop. You can then add more signals inside the loop to allow more trains to enter, but you need the ones at the junction.
At each junction actually.

-edit
This is what I was trying to describe. https://snag.gy/5CYr6d.jpg
RS = Regular Signal, CS = Chain signal.

This setup should keep your junctions clear from blocking trains, but you probably need extra Regular Signals, as I have added in the loop above the bottom one.
However you will most probably still run into problems with trains blocking each other. My advice would be to go for double tracks, one for each direction.
Build a main track and put your stations on sidelines connecting to that main track..

I hope that helped at all.