B80 is used to drive the urea pump. The pressure building, injection and pumping of the urea pump are normal. Prove that the liquid circuit, pump, nozzle and are normal .
Check the plug of urea pump and find that the plug is corroded. Replace the plug of urea pump.
When the fault code is cleared, the open circuit fault code of the reverse valve of the urea pump cannot be cleared. Check the circuit diagram and confirm that pin 11 of urea pump plug is powered by reverse valve and connected to ECU pin K30 .
Measure No. 11 pin of urea pump harness and there is no 24V voltage. Measure ecuk30 pin and there is 24V voltage. Because 24V output is measured at the ECU end, it is judged that there is a circuit fault of open circuit or grounding between the urea pump and the ECU connecting harness.
Delong harness is all white. Pull out the wire to check the harness according to the harness number and find the breakpoint at the girder.
Repair the harness. After clearing the fault, the system is normal. Using the drive test function, the pressure building, injection and reverse pumping after driving are normal. After reassembly, the commissioning is normal and the fault is eliminated.
Today’s fault cases are shared here. Thank you for your attention. See you next time!