I had a hopper wagon, and when he is above a hopper it does not send any redstone signal to the comparator next to the hopper (it sends a redstone signal of power 1 = not enough to stop the wagon until its hopper is empty).

I don't know why you changed the original code... This mod literally fucked up all the track system in minecraft.

Could you fix this please?

I can't do a recolector because it doesn't work properly. Wagon does not stop over the hopper until it is empty

Lol comparator outputs for minecarts are passed with detectors. Redstone comparators do not detect minecarts.

I mean, the redstone track over the hopper, and the hopper near the comparator...

Hmm, need to check if this is a design issue of railcraft. try replacing the comparator with a redstone wire and see the output strength.

Some pictures would help.

hmm, the comparator output does not update with the cart's inventory change.

What is it attached to? The hopper?

The issue here is that Detector TrackKits don't implement the Comparator integration. This is an oversight on our part.