A nuance ignition problems

I have the following problem with a Matiz: when I try to start the car, it doesn't start because it's not injecting fuel. I installed a new fuel pump, but nothing changed. When I measure the signal at the injectors, I have a positive signal but no negative pulse. I checked the distributor, and it's not the problem. I also tried the computer, and it's not the same. I changed the sensors, and still nothing. Could someone tell me what it could be? I'm pretty sure it's a wire, but I don't have the electrical manual. If anyone has it and could share it with me, I would be very grateful. Please send it to the following email address. . :unsure:

Hi, look, the first thing you need to do is go step by step to find the problem quickly. Based on what you've described, the problem is with the fuel injection system. The first thing is to determine if the fault is due to a lack of fuel supply to the rail or a lack of electrical power to the injectors (electronics). To do this, disconnect the fuel inlet line to the rail and check the pressure; it should be greater than 40 psi. If you don't have a pressure gauge, connect the line directly to a gallon container and open the fuel switch. Keep in mind that depending on the injection system, the pump will send pressure with the switch open or when the engine is cranking. If the pressure is good, then you can rule that out and focus on the injectors. These have two wires: 12V and a ground signal. Try cranking the 12V line; if it's good, check the ground with a logic probe. This will determine if there is actually a signal from the computer. If all of this is okay, you should remove and check the injectors and the fuel pressure regulator. In my personal opinion... If you've already replaced the fuel pump, the problem could be with the electrical supply. Check the 12V at the power cables. Remember to try starting the engine to test it.
Best of luck, and hopefully you can fix it. Let us know how it goes.

Thanks for the subject, the problem was lack of land to the computer