What is the reason for the urea tank not making noise after parking?
1 Answers
When there is no noise after parking, it indicates a malfunction in the urea pump. The urea pump continues to operate after the engine is turned off to return the unused urea in the pipes back to the urea tank. Otherwise, the urea in the pipes may crystallize, affecting normal use during the next operation. Therefore, the urea pump continues to work for a while after the vehicle is turned off before stopping automatically. Below is an introduction to the urea pump: 1. Working principle and internal composition of the urea pump The urea pump is the core component of the SCR system, known as the "urea dosing pump." Its main function is to pump the urea solution from the urea tank and transport it to the nozzle through the delivery pipe. 2. Working principle of the urea pump The internal composition of the urea pump mainly consists of a diaphragm pump, electromagnetic reversing valve, pressure sensor, urea filter, electric heating system, lead frame, and other components. The exterior is composed of three urea solution pipelines: the spray pipe, return pipe, and inlet pipe. 3. Internal composition of the urea pump There are two types of urea pumps: one is the airless urea pump represented by Bosch, and the other is the air-assisted urea pump represented by Emitec and Cummins.