B2BEmersonEIMS serves commercial, industrial, healthcare, telecom, hospitality, government & contractor clients.• Engineering-led • SLA-backed • Documented commissioning
Keyboard Shortcuts
Every Atlas Copco engine fault code in our verified reference — 75 codes, 10 of them with a documented remedy. Find your code in the table, read the likely causes, then work the remedy. If it is beyond a field fix, our workshop in Embakasi repairs Atlas Copco controllers and engines at board level.
Covers: QAS Series · QEP Series · QES Series · WP Series
| Code | Fault | Likely cause | Remedy |
|---|---|---|---|
| 101 | Synchronization signal error (crankshaft/camshaft) | The crankshaft and camshaft sensor signals are out of sync; causing abnormal fuel injection and difficult starting. | — |
| 102 | ECU internal time treatment unit error | The ECU’s internal timing unit has failed; preventing the engine from starting. | — |
| 103 | Low engine power with black smoke | Insufficient engine power with black exhaust smoke due to air intake or sensor issues.; over-fueling; injector faults). Reset the fault via the ECU diagnostic tool and restart. Consult the Weichai WP Series or a technician if unresolved.[](s://d/document/438489972/Weichai-Power-Engine-Euro-III-Flash-Code-List) | Inspect the air intake system for blockages or a clogged air filter; clean or replace as needed. Test the air intake pressure sensor and wiring for faults; replace if defective. Check for fuel system issues (e.g. |
| 104 | Low battery voltage | The battery voltage is too low (<6V for 12V systems); affecting ECU and starter operation. | — |
| 105 | High battery voltage | The battery voltage is too high (>36V for 24V systems); indicating overcharging. | — |
| 106 | Fuel supply issue | There is no fuel in the tank or the fuel tank switch is off; preventing engine start. | — |
| 107 | Fuel pipeline or filter blockage | The fuel pipeline or filter is clogged; restricting fuel flow to the engine. | — |
| 108 | Starter relay failure | The starter relay is malfunctioning; preventing the engine from cranking. | — |
| 109 | Low oil pressure | The engine oil pressure is below the safe threshold; triggering a warning or shutdown. | — |
| 110 | High coolant temperature | The engine coolant temperature exceeds the safe limit (e.g.; >100°C) | — |
| 111 | Water in fuel | Water is detected in the fuel filter; risking engine damage. | — |
| 112 | Accelerator pedal sensor 1 high voltage | The No. 1 accelerator pedal position sensor circuit has a voltage above normal or is shorted to a high voltage source. | Test the accelerator pedal position sensor with a multimeter for proper voltage (0–5V range); replace if defective. Inspect sensor wiring for shorts to power or damage. Check the ECM harness for faults. Reset the fault via the ECU diagnostic tool and restart. to the Weichai WP Series or a technician if unresolved.[](s://dbdieselgenerator/generator-sets/typical-fault-codes-of-generator-sets.html) |
| 113 | Accelerator pedal sensor 1 low voltage | The No. 1 accelerator pedal position sensor circuit has a voltage below normal or is shorted to a low voltage source. | Test the accelerator pedal position sensor with a multimeter for proper voltage (0–5V range); replace if defective. Inspect sensor wiring for shorts to ground or opens. Check the ECM harness for faults. Reset the fault via the ECU diagnostic tool and restart. Consult the Weichai WP Series or a technician if unresolved.[](s://dbdieselgenerator/generator-sets/typical-fault-codes-of-generator-sets.html) |
| 114 | MAP sensor failure | The manifold absolute pressure (MAP) sensor is malfunctioning; affecting air intake monitoring. | — |
| 115 | IAT sensor failure | The intake air temperature (IAT) sensor is malfunctioning; providing incorrect readings. | — |
| 116 | ECT sensor failure | The engine coolant temperature (ECT) sensor is malfunctioning; affecting temperature monitoring. | — |
| 117 | TPS sensor failure | The throttle position sensor (TPS) is malfunctioning; affecting throttle control. | — |
| 118 | Knock sensor failure | The knock sensor is malfunctioning; affecting engine knock detection. | — |
| 1011 | Engine air intake temperature high | The air intake temperature exceeds the safe limit; affecting engine performance. | — |
| 1012 | Governor failure | The engine governor is malfunctioning; affecting speed control. | — |
| 1013 | Crankshaft position sensor failure | The crankshaft position sensor is malfunctioning; affecting engine timing. | — |
| 1014 | Camshaft position sensor failure | The camshaft position sensor is malfunctioning; affecting engine timing. | — |
| 1015 | Fuel pressure low | The fuel system pressure is below the required threshold; affecting engine performance. | — |
| 1016 | Alternator phase sequence error | The alternator phase sequence is incorrect; causing electrical output issues. | — |
| 1017 | Control module internal fault | The control module has detected an internal hardware or software error.; Power cycle the generator by disconnecting the battery for 30 seconds and reconnecting. Check for firmware updates for the control module in the Atlas Copco QAS . Inspect module wiring for faults (e.g.; shorts; opens). If the fault persists | replace the control module. Reset the fault on the control panel and restart. Consult the Atlas Copco QAS or a technician if unresolved. |
| 1018 | Oil filter restriction | The oil filter is clogged; reducing oil flow and affecting engine performance. | — |
| 1019 | Starter relay failure | The starter relay is malfunctioning; preventing engine cranking. | — |
| 1020 | CAN bus communication failure | The CAN bus communication with the engine control unit or other modules has failed.; opens; or loose connections. Verify all connected modules (e.g.; ECU; control panel) are powered and configured correctly. Reset the control panel (e.g. | Inspect CAN bus wiring and connectors for shorts |
| 1021 | Engine fuel temperature high | The fuel temperature exceeds the safe operating limit; affecting engine performance. | — |
| 1022 | Alternator bearing failure | The alternator bearings are failing; causing excessive noise or heat. | — |
| 1023 | Engine shutdown failure | The engine fails to shut down properly after a shutdown request.; stuck solenoid; open circuit). Verify no external signals (e.g.; ATS) are preventing shutdown. Test the control signal from the control panel. Reset the fault on the control panel and test shutdown. Consult the Atlas Copco QAS or a technician if unresolved. | Inspect the shutdown solenoid and wiring for faults (e.g. |
| 1024 | Engine coolant pressure sensor failure | The coolant pressure sensor is malfunctioning; providing incorrect readings. | — |
| 1025 | Alternator voltage sensor failure | The alternator voltage sensor is malfunctioning; affecting voltage monitoring. | — |
| 1026 | Engine speed sensor failure | The engine speed sensor is malfunctioning; affecting speed monitoring. | — |
| 1027 | Fuel temperature sensor failure | The fuel temperature sensor is malfunctioning; providing incorrect readings. | — |
| 1028 | Control panel communication port failure | The control panel’s communication port (e.g.; RS485) is malfunctioning | — |
| 1029 | Engine turbocharger boost pressure low | The turbocharger boost pressure is below the expected threshold; affecting engine performance. | — |
| 1030 | Alternator circuit breaker trip | The alternator circuit breaker has tripped due to overload or fault.; reduce if exceeding the generator’s capacity. Check alternator output cables for shorts or damage. Test the circuit breaker for proper operation | Inspect the electrical load; reset or replace if defective. Verify load connections for faults. Reset the fault on the control panel and restart. Consult the Atlas Copco QAS or a technician if unresolved. |
| 2009 | Low coolant level | The engine coolant level is below the safe threshold; triggering a warning or shutdown. | — |
| 2010 | Engine misfire | The engine control unit detects a misfire; indicating combustion irregularities. | — |
| 2011 | Fuel solenoid valve failure | The fuel solenoid valve is not operating; affecting fuel delivery. | — |
| 2012 | Engine preheating relay failure | The engine preheating relay (e.g.; for glow plugs) is malfunctioning | — |
| 2013 | Alternator frequency sensor failure | The alternator frequency sensor is malfunctioning; affecting frequency monitoring. | — |
| 2014 | Engine oil temperature sensor failure | The oil temperature sensor is malfunctioning; providing incorrect readings. | — |
| 2015 | Fuel pressure sensor failure | The fuel pressure sensor is malfunctioning; affecting fuel system monitoring. | — |
| 2016 | Control panel power supply failure | The control panel power supply is outside acceptable limits.; battery or auxiliary supply); ensure proper voltage (e.g.; 12V or 24V). Inspect power supply wiring for shorts; opens; or damage. Test the battery or power module | Check the control panel power source (e.g.; replace if faulty. Reset the fault on the control panel and restart. to the Atlas Copco QES or a technician if unresolved. |
| 2017 | Engine oil level sensor failure | The oil level sensor is malfunctioning; providing incorrect level readings. | — |
| 2018 | Alternator phase imbalance sensor failure | The sensor monitoring alternator phase balance is malfunctioning.; opens; or loose connections. Verify phase balance with a multimeter on the alternator output. Reset the fault on the control panel and restart. to the Atlas Copco QES or a technician if unresolved. | Test the phase balance sensor with a multimeter for proper operation; replace if defective. Inspect sensor wiring for shorts |
| 2019 | Engine oil pressure sensor failure | The oil pressure sensor is malfunctioning; providing incorrect pressure readings. | — |
| 2020 | Alternator overcurrent sensor failure | The sensor monitoring alternator current is malfunctioning; affecting overload detection. | — |
| 2021 | Engine coolant temperature sensor failure | The coolant temperature sensor is malfunctioning; providing incorrect readings. | — |
| 2022 | Fuel level sensor failure | The fuel level sensor is malfunctioning; providing incorrect fuel level readings. | — |
| 2023 | Engine air intake temperature sensor failure | The air intake temperature sensor is malfunctioning; affecting performance monitoring. | — |
| 2024 | Engine turbocharger actuator failure | The turbocharger actuator is malfunctioning; affecting boost control. | — |
| 2025 | Control panel memory error | The control panel has detected a memory corruption or configuration error.; Power cycle the generator by disconnecting the battery for 30 seconds and reconnecting. Check for firmware updates for the control panel in the Atlas Copco QES . Reset the control panel configuration to factory settings if possible. If the fault persists | replace the control panel. Reset the fault and restart. to the Atlas Copco QES or a technician if unresolved. |
| 3001 | Fuel solenoid valve failure | The fuel solenoid valve is not operating; affecting fuel delivery. | — |
| 3002 | Engine preheating failure | The engine preheating system (e.g.; glow plugs) is not functioning | — |
| 3003 | Control module communication failure | The control module has lost communication with external devices (e.g.; ECU | — |
| 3004 | Oil temperature high | The engine oil temperature exceeds the safe limit; triggering a warning or shutdown. | — |
| 3005 | Fuel filter restriction | The fuel filter is clogged; reducing fuel flow and affecting engine performance. | — |
| 3006 | Alternator bearing temperature high | The alternator bearing temperature exceeds the safe limit; indicating potential wear. | — |
| 3007 | Low coolant pressure | The engine coolant pressure is below the safe threshold; indicating a potential issue. | — |
| 3008 | Engine coolant level sensor failure | The coolant level sensor is malfunctioning; providing incorrect level readings. | — |
| 3009 | Exhaust temperature sensor failure | The exhaust temperature sensor is malfunctioning; affecting temperature monitoring. | — |
| 3010 | Alternator temperature sensor failure | The alternator temperature sensor is malfunctioning; affecting temperature monitoring. | — |
| 3011 | Engine air intake pressure sensor failure | The air intake pressure sensor is malfunctioning; affecting engine performance monitoring. | — |
| 3012 | Fuel pump relay failure | The fuel pump relay is malfunctioning; affecting fuel delivery. | — |
| 3013 | Control panel display failure | The control panel display is malfunctioning; preventing proper monitoring. | — |
| 3014 | Engine injector failure | One or more fuel injectors are malfunctioning; affecting combustion. | — |
| 3015 | Engine throttle actuator failure | The throttle actuator is malfunctioning; affecting engine speed control. | — |
| 3016 | Alternator cooling fan failure | The alternator cooling fan is not operating; causing potential overheating. | — |
| 3017 | Engine fuel injector circuit failure | The fuel injector circuit is malfunctioning; affecting fuel delivery. | — |
| 3018 | Control panel relay failure | One or more control panel relays (e.g.; for starting or shutdown) are malfunctioning. | — |
| 3019 | Engine exhaust gas recirculation valve failure | The EGR valve is malfunctioning; affecting emissions and performance. | — |
| 3020 | Engine cooling fan failure | The engine cooling fan is not operating; causing potential overheating. | — |
Codes and descriptions are industry-standard identifiers reproduced for identification only. This reference is not affiliated with or endorsed by Atlas Copco; for official procedures always refer to the manufacturer’s service manual for your specific engine. A dash means our registry holds no verified entry for that column — we publish the gap rather than fill it in.
Send us the code and the engine serial. We diagnose Atlas Copco sets on site across all 47 counties, and repair controllers at board level on the bench in Embakasi.