What does low rail pressure 15718 mean?

[SanAyla]

Low rail pressure is mainly caused by plunger wear, common rail pressure regulator failure, or computer board failure. Here are the related introductions: 1. Excessive carbon deposits: Too much carbon deposits in the intake system or at the root of the intake valve result in an overly lean air-fuel mixture during cold starts. 2. Severely dirty throttle body, insufficient air intake: Clogged fuel lines or excessive water in the fuel can lead to low rail pressure; all cylinder injectors are connected to a common fuel pipe (referred to as the fuel rail), which always maintains constant pressure—if damaged, it will cause low rail pressure; if the injectors are clogged or damaged, it can also lead to low rail pressure, etc.