**Introduction**
As diesel engines become more advanced and environmentally friendly, aftertreatment systems play a crucial role in ensuring compliance with emissions standards. The John Deere / Hitachi 870 is a workhorse in the industry, known for its power and efficiency. However, like any complex machinery, it's not immune to issues. In this technical article, we delve into the DEF (Diesel Exhaust Fluid) pump-related fault codes 10533-12 and 10042-12 that affect the John Deere / Hitachi 870, and provide step-by-step troubleshooting guidance to rectify these issues.
**Understanding Fault Codes 10533-12 and 10042-12**
Fault code 10533-12 is indicative of low DEF pressure, a critical parameter for proper functioning of the Selective Catalytic Reduction (SCR) system. This deficiency can lead to incomplete NOx reduction and result in fault code 10042-12, indicating SCR inducementāan engine derate caused by the earlier low DEF pressure fault.
**Troubleshooting Steps**
1. **Inspect and Clean the DEF Tank**:
Contamination in the DEF tank can hinder the proper flow of DEF. Begin by inspecting the tank and ensuring it is clean and free from debris. Replace the suction filter to prevent clogs that could further impede DEF flow.
2. **Check DEF Lines for Cracks and Breaks**:
Damaged DEF lines can lead to air being sucked into the system, reducing pressure. Thoroughly inspect all DEF lines for any signs of cracks or breaks. Replace any damaged lines to restore proper functionality.
3. **Accessing the Service Menu**:
To initiate the troubleshooting process, enter the service menu by pressing and holding the number 9 on the keypad, and then click the scroll wheel in the center.
4. **Monitoring DEF Parameters**:
In the service menu, locate and display DEF pressure, DEF pump aperture s/m, and SCR temperature. These parameters will help you diagnose the issue.
5. **Increasing Exhaust Temperature**:
To initiate a priming sequence, increase the exhaust temperature. This will help with DEF circulation and priming.
6. **Monitoring DEF Pump Aperture and Pressure**:
As the priming sequence begins, observe the DEF pump aperture s/m. As it increases above zero, you should notice the DEF pressure rising to around 9000hPa. The pump aperture should stabilize at a duty cycle of 20-30%, indicating proper pump operation.
7. **Listening to the Pump**:
If you're not observing DEF pressure even when the pump aperture is above zero, use a stethoscope to listen for the pump's operation. If the pump is not running, replacement is necessary.
8. **Checking for Leaks and DEF Level**:
The pump should build pressure if it is commanded on (verified by reading pump aperture).Ā Ā If the pump is running but pressure isn't building, recheck your DEF lines for leaks. Also, ensure that the DEF level is adequate.Ā If your pump is running, but still no pressure and all other variables are eliminated, replace the pump.
9. **Considering DEF Pump Replacement**:
If all previous steps have been taken and the issue persists, it's highly likely that the DEF pump has failed. At AftertreatmentParts.com, we stock a wide range of replacement DEF pumps specifically designed for the John Deere / Hitachi 870.
**Conclusion**
Maintaining the proper functionality of your John Deere / Hitachi 870's aftertreatment system is vital for emissions compliance and optimal performance. By understanding and addressing DEF pump-related fault codes like 10533-12 and 10042-12, you can minimize downtime and ensure that your equipment operates efficiently. Remember, our team at AftertreatmentParts.com is here to assist you. Whether you have questions about troubleshooting or need to order a replacement DEF pump, don't hesitate to reach out. Your commitment to resolving these issues contributes to a cleaner environment and a smoother workflow.
