A persistent “Warn Engine” light on an International truck’s dashboard can be a frustrating experience. This article details a real-world troubleshooting process for this issue, focusing on a faulty DPF pressure sensor and a water leak in the wiring harness. Understanding this problem and its solution can save you time and money.
Diagnosing the Problem: DPF Pressure Sensor Codes
The “Warn Engine” light initially indicated a problem with the Diesel Particulate Filter (DPF) pressure sensor, preventing the DPF from regenerating. Replacing both pressure sensors didn’t resolve the issue, and further investigation revealed a short circuit in the wiring harness receiving information from multiple sources. Interestingly, the code cleared itself overnight but reappeared after a truck wash.
Finding the Culprit: A Water Leak in the Wiring Harness
Suspecting a water leak, the focus shifted to the wiring harness connectors. The DPF sensor harness, consisting of two pieces connected under the cab near the frame, was inspected. Water was found inside the connection. Cleaning and drying the connection with an electrical contact cleaner eliminated the code. The connection was then sealed with silicone to prevent further water intrusion.
A Potential Widespread Issue and Temporary Fix
This specific water leak in the DPF sensor wiring harness connection might be a more common problem in International trucks than initially thought. The truck manufacturer has been notified and is investigating a permanent solution. In the meantime, if your International truck experiences intermittent “Warn Engine” lights, especially after washing, have a mechanic check this connection for water tightness. Even with seemingly intact weather protection, water can still penetrate and cause issues.
Conclusion: Addressing the Warn Engine Light
This firsthand account highlights the importance of thorough diagnostics when dealing with a “Warn Engine” light on an International truck. While replacing components might seem like the logical first step, checking for seemingly simple issues like water leaks in electrical connections can save time and prevent unnecessary repairs. This case suggests a potential design flaw that International is addressing. If you encounter this problem, sharing this information with your mechanic can expedite the troubleshooting process. Hopefully, a service advisory will be issued soon to provide a permanent fix for this issue.
