Suzuki Grand Nomade 2008. No prende, no hay check engine. Parpadean luces en el tablero, sin chispa

It won't start. When the key is turned to ON, some dashboard lights flash, but the check engine light doesn't illuminate. This is very important in most vehicles because when the key is turned to ON, the light should illuminate, indicating that the computer is "on." As a basic check, it was found that there was no power to the fuel pump or the injectors. These are powered by a relay located in the engine compartment, called the MAIN RELAY. The MAIN RELAY wasn't activating; it needs a negative signal from the engine control unit (ECU). The J20 engine diagram was located, the diagram was analyzed, and after checking all the main power supply lines to the ECU, it was found that a 12V wire was corroded/broken. The wire was repaired, but the necessary signal was still not present. After performing all the tests, the only remaining option was to replace or repair the engine control unit. This was done, and the vehicle returned to normal operation.