Check the startup line! When pressing the start button, use a multimeter to measure whether there is 12v voltage in the relay signal line (starting power supply)! The relay is broken! There is no problem with the wiring and start button! In addition, Dongfeng Big Sheep has a side support switch. It can only be started when the temples are retracted! Check if it's broken! The cylinder you are talking about is a relay. You started it with a short circuit. It shows that the circuit from relay to starter is normal!