Why is the urea pump silent after a China V vehicle is turned off?
3 Answers
If the urea pump does not make any sound after the engine is turned off, it indicates that the pump is damaged. Below are specific details about the urea pump: 1. Introduction: The urea pump is a crucial component of the urea solution injection metering system. Its primary function is to extract urea solution from the urea tank, maintain a certain pressure, and then deliver it to the injection unit to meet the flow and pressure requirements of the injection metering system. 2. Composition and Principle: It mainly consists of a motor, supply pump, reverse pump, switch valve, pressure chamber, throttle orifice, etc. The pump operates in two states: supply and emptying. When supplying liquid to the urea injection system, the motor drives the supply pump to transport urea solution from the urea tank to the pressure chamber. A portion of the urea solution is used for injection, while another portion flows back to the urea tank through the throttle orifice.
As a veteran driver operating a China V standard truck, I've encountered this issue several times. If the urea pump makes no sound after the engine shuts off, it's usually abnormal because normally it should continue running briefly to clean the pipelines. The most common cause is a blown fuse, especially if your vehicle has been recently washed or exposed to heavy rain, as short circuits in wiring can easily melt fuses. Next, inspect the pump itself - the motor might be stuck or worn out, which often happens due to prolonged vibration during long-haul driving. Loose wiring connectors are also frequent culprits, since the urea tank area tends to get damp, leading to poor contact. Don't rule out control unit malfunctions either, such as sensor signal errors causing the system to mistakenly think operation isn't needed. Long-term neglect can cause crystallization and nozzle clogging, resulting in higher repair costs and affecting emission tests. Last time at the repair shop, mine turned out to be a fuse issue - replacement fixed it immediately. I recommend checking the urea system during regular maintenance to prevent minor issues from escalating.
As an environmentally conscious car owner, I'm quite concerned that my China V vehicle's urea pump doesn't make any sound after shutdown. The urea pump is supposed to operate for several minutes after turning off the engine to prevent solution residue crystallization and ensure system cleanliness. If there's no sound, it might indicate a power supply interruption, such as low battery voltage or alternator issues, causing insufficient system power after vehicle shutdown. Pump module failure itself could also be a factor, including internal motor damage or carbon buildup blockage. Control software bugs shouldn't be overlooked either, as system logic errors may prevent program triggering. These issues can lead to emission control failure, increasing NOx pollution, not to mention startup difficulties caused by clogged pipelines. I've developed the habit of listening for the pump sound before each startup - if it's silent, I immediately visit a professional workshop to check fault codes with a diagnostic tool. Proper maintenance can also save fuel and money.
