Understanding SPN 5435 SPN 5435 is a diagnostic trouble code (DTC) related to issues with the Diesel Exhaust Fluid (DEF) system. It typically indicates a "Non DEF flow situation" where the DEF pump speed is low. The exact description may vary by vehicle make and model. In our workshop, we've encountered the SPN 5435 fault
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Introduction Fault Code SPN 1639 is related to issues with the engine fan speed on vehicles equipped with electronic engine control modules (ECM). When this code is triggered, the ECM has detected a problem with the fan speed signal, indicating the cooling fan is not operating as expected. While SPN 1639 requires prompt attention to
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What is Fault Code SPN 1761? Fault Code SPN 1761 is a generic diagnostic trouble code (DTC) that indicates a problem with the Aftertreatment 1 Diesel Exhaust Fluid (DEF) Tank Level Sensor. This code applies to many diesel vehicles equipped with Selective Catalytic Reduction (SCR) systems for emissions control, including trucks, buses, and some passenger
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Fault Code SPN 4354: Diesel Exhaust Fluid (DEF) Line Heater 1 Circuit Urgency Level: Medium If your vehicle is displaying fault code SPN 4354, it indicates an issue with the DEF Line Heater 1 circuit. While the vehicle can still be driven cautiously, this fault should be diagnosed and repaired promptly to avoid potential issues
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Urgency and Severity When the SPN 3610 fault code appears, it indicates an issue with the Diesel Particulate Filter (DPF) inlet or outlet pressure sensor circuit. The urgency depends on the specific situation: In our workshop, we've encountered Fault Code SPN 3610 quite frequently across various vehicle makes. With American trucks like Freightliner and Peterbilt,
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What is Fault Code SPN 5394? SPN 5394 is a generic diagnostic trouble code that indicates a problem with the diesel exhaust fluid (DEF) dosing valve or related components in the selective catalytic reduction (SCR) system. This code applies to many makes and models of diesel vehicles equipped with SCR systems to reduce NOx emissions.
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Understanding Fault Code SPN 4335 Fault code SPN 4335 indicates an issue with the Exhaust Gas Recirculation (EGR) position sensor circuit. When this code is triggered, it's important to diagnose and address the problem promptly to prevent potential engine damage. However, in most cases, you can safely drive the vehicle to a repair shop unless
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Introduction Fault Code SPN 3031 indicates a malfunction with the Diesel Exhaust Fluid (DEF) tank temperature sensor circuit. While this issue requires prompt attention from a qualified mechanic, in most cases it is safe to continue driving the vehicle cautiously for a short period until a repair can be scheduled. However, ignoring the problem for
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Introduction Fault Code SPN 4094 is a generic diagnostic trouble code (DTC) that indicates the NOx (nitrogen oxide) limits have been exceeded in the exhaust system. This code commonly appears on heavy-duty trucks and buses equipped with diesel engines and SCR (Selective Catalytic Reduction) aftertreatment systems. When SPN 4094 is triggered, the vehicle may enter
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Urgency and Driving Considerations If your vehicle logs a P0224 fault code, you should stop driving immediately and have the vehicle towed to a mechanic or dealership for diagnosis and repair. Continuing to drive with this fault could lead to poor engine performance, rough running, stalling, or even an inability to control the engine speed.
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