Mercury Smartcraft Fault Codes List Hot! | TESTED | Release |

Codes appear as:

| Code | SPN | FMI | Description | |------|-----|-----|-------------| | 12-1 | 110 | 1 | Engine coolant temperature sensor – voltage too low (shorted) | | 12-2 | 110 | 0 | Coolant temp sensor – voltage too high (open circuit) | | 13-1 | 105 | 1 | Intake air temp sensor – voltage low | | 13-2 | 105 | 0 | Intake air temp sensor – voltage high | | 15-1 | 174 | 1 | Fuel temperature sensor – voltage low | | 15-2 | 174 | 0 | Fuel temp sensor – voltage high | | 22-1 | 100 | 1 | Oil pressure sensor – voltage low | | 22-2 | 100 | 0 | Oil pressure sensor – voltage high | | 23-1 | 100 | 1 | Low oil pressure (actual) – engine may shut down | | 31-1 | 157 | 0 | MAP sensor (Manifold Absolute Pressure) – voltage high | | 31-2 | 157 | 1 | MAP sensor – voltage low |

Return for service soon; check battery health and charging system. Overtemperature (Critical) : Engine is overheating. mercury smartcraft fault codes list

| Fault Code | Description | Typical Cause / Action | | :--- | :--- | :--- | | | Engine Overheat | Engine temp critical (>200°F+). Check water pump impeller, thermostat, and poppet valve. | | Code 42 | Low Oil Pressure | Triggered by the oil pressure sender. Stop engine immediately. Check oil level and pressure relief valve. | | Code 43 | Guardian Mode Active | Not a specific fault, but a status indicating the ECU has limited RPM (usually to 2000-3000) to protect the engine. Look for other active codes. |

The Mercury SmartCraft fault codes list provided in this report is a comprehensive guide to help identify and troubleshoot engine issues. By understanding the fault codes and their possible causes, boat owners and mechanics can quickly diagnose and repair problems, reducing downtime and increasing engine performance. Codes appear as: | Code | SPN |

| Code | SPN | FMI | Description | |------|-----|-----|-------------| | 99-1 | 2000 | 9 | SmartCraft CAN bus – missing data from ECU | | 99-2 | 2001 | 2 | Gauge network – no response from tachometer | | 99-3 | 2002 | 12 | Faulty SmartCraft junction box | | 100-1 | 630 | 2 | ECU internal memory error | | 100-2 | 628 | 12 | Injector driver chip fault (ECU) |

: For more precise data, technicians use the Mercury Marine CDS G3 diagnostic software. Common Mercury SmartCraft Fault Codes Check water pump impeller, thermostat, and poppet valve

: The engine uses audible signals to alert you to issues even if you aren't looking at the gauge. A single beep typically means "all systems clear," while a continuous tone or a repeating series of beeps indicates a fault.

| Code | SPN | FMI | Description | |------|-----|-----|-------------| | 18-1 | 168 | 0 | System voltage – high (over 16V) | | 18-2 | 168 | 1 | System voltage – low (under 9V) | | 19-1 | 167 | 3 | Alternator output – no charge detected | | 21-1 | 167 | 4 | Stator / regulator – excessive AC ripple |