NetworkU0300
SeriousSeverity: Serious - have it checked soon
Internal Control Module Software Incompatibility
Key terms: Control module: a small computer that runs one part of the car · SAE J2012: the standard generic code list
1What it means in plain English
Control modules in the car cannot communicate with each other over the vehicle network.
2Common causes
- Wiring or connector fault on the communication bus
- Faulty control module
- Low battery voltage or poor ground
- Water ingress in a connector or module
- Aftermarket device interfering with the bus
3Can I drive?
Serious · drive with care
The car may run normally or may not run at all. If the module that has lost communication controls steering, brakes, park brake, charging or engine cooling, drive only if those systems feel normal; stop safely if the steering becomes heavy, a brake warning appears, or the engine temperature climbs. If the car will not start or runs badly, have it towed.
This page gives general information. It is not professional advice. For a definite diagnosis and a repair quote, ask a qualified mechanic to inspect the car.
4Brand data 36
| Brand | Code | Description | System |
|---|---|---|---|
| Ashok Leyland CV | U0300 | Direct Ozone Reduction Catalyst. Wearing Sensor. Operation Failure Brand | Network |
| BAIC Motor | U0300 | Internal Control Module Software Incompatibility Brand | Network |
| Mercedes-Benz | U0300 | Internal Control Module Software Incompatibility SAE | Network |
| BYD | U0300 | Communication with gateway fault Brand | Network |
| Chery | U0300 | Internal Control Module Software Incompatibility Brand | Network |
| Chrysler | U0300 | Internal Control Module Software Incompatibility SAE | Network |
| Daewoo | U0300 | Internal Control Module Software Incompatibility Brand | Network |
| Daihatsu | U0300 | ACC variant abnormal Brand | Network |
| DFFS | U0300 | EEPROM fault Brand | Network |
| DFFX | U0300 | Internal Control Module Software Incompatibility Brand | Network |
| DFXK | U0300 | Internal Control Module Software Incompatibility Brand | Network |
| EOBD | U0300 | Inkompatibel programvara i intern styrmodul Brand | Network |
| Ford | U0300 | Internal Control Module Software Incompatibility SAE | Network |
| Geely | U0300 | CAN communication not compatible Brand | Network |
| GM | U0300 | Internal Control Module Software Incompatibility Brand | Network |
| Great Wall | U0300 | Internal Control Module Software Incompatibility Brand | Network |
| Hafei | U0300 | Internal Control Module Software Incompatibility Brand | Network |
| Holden | U0300 | Internal Control Module Software Incompatibility Brand | Network |
| Honda | U0300 | Internal Control Module Software Incompatibility SAE | Network |
| Hyundai | U0300 | Internal Control Module Software Incompatibility SAE | Network |
| Land Rover | U0300 | Internal Control Module Software Incompatibility SAE | Network |
| Mazda | U0300 | Internal Control Module Software Incompatibility SAE | Network |
| Mitsubishi | U0300 | Internal Control Module Software Incompatibility SAE | Network |
| Nissan | U0300 | Internal Control Module Software Incompatibility SAE | Network |
| Opel | U0300 | Internal Control Module Software Incompatibility Brand | Network |
| Perodua | U0300 | ACC variant abnormal Brand | Network |
| Peugeot | U0300 | Internal Control Module Software Incompatibility SAE | Network |
| Porsche | U0300 | Internal Control Module Software Incompatibility SAE | Network |
| Proton | U0300 | Internal Control Module Software Incompatibility SAE | Network |
| Saab | U0300 | Internal Control Module Software Incompatibility Brand | Network |
| MG (SAIC) | U0300 | Limp Home Brand | Network |
| Sprinter | U0300 | Internal Control Module Software Incompatibility SAE | Network |
| Suzuki | U0300 | CAN COMM DATA Brand | Network |
| Tata | U0300 | Internal Control Module Software Incompatibility Brand | Network |
| Toyota | U0300 | Internal control module software is incompatible Brand | Network |
| Volkswagen | U0300 | SAE: Internal Control Module Software Incompatibility Brand | Network |
Legend: SAE is the generic J2012 description; Brand is text taken from that manufacturer’s data. Manufacturer rows keep the wording and language of the source data, and non-English text is tagged so screen readers pronounce it correctly.
5Extended variant codes 60
These 7-character codes are manufacturer-specific variants of U0300 and may be reported by some scan tools.
| Brand | Code | Description | System |
|---|---|---|---|
| Mercedes-Benz | U030000 | CAT1 or CAT2 reset occured Brand | Network |
| SsangYong | U030000 | Faulty system(inconsistency) Brand | Network |
| Volkswagen | U030000 | Other control modules incompatible with engine control module coding Brand | Network |
| Mercedes-Benz | U030001 | E3 Sw ErrorSopc Brand | Network |
| Mercedes-Benz | U030002 | An internal fault has occurred in the control unit software. General Signal Failure. Brand | Network |
| Mercedes-Benz | U030004 | software error in variable pool (only development) Brand | Network |
| Mercedes-Benz | U030005 | Lockstep fault Brand | Network |
| Mercedes-Benz | U030006 | software error in time based memory management (only development) Brand | Network |
| Mercedes-Benz | U030007 | software error in errorhandler (only development) Brand | Network |
| Mercedes-Benz | U030009 | An internal fault has occurred in the control unit software. There is a component fault. Brand | Network |
| Mercedes-Benz | U030031 | An internal fault has occurred in the control unit software. No Signal. Brand | Network |
| Mercedes-Benz | U030041 | An internal fault has occurred in the control unit software. General Checksum Failure Brand | Network |
| Mercedes-Benz | U030042 | An internal fault has occurred in the control unit software. There is a general memory error. Brand | Network |
| Mercedes-Benz | U030043 | An internal fault has occurred in the control unit software. There is an error in the additional memory. Brand | Network |
| Mercedes-Benz | U030046 | An internal fault has occurred in the control unit software. Calibration / Parameter Memory Failure Brand | Network |
| Mercedes-Benz | U030047 | Error in task monitoring Brand | Network |
| Smart | U030047 | No description available | Network |
| Mercedes-Benz | U030048 | software error in buffer management Brand | Network |
| Mercedes-Benz | U030052 | Array output indicating Inverter Temperature Sensor Noisy fault symptom status for each of the available inverter temperature sensors. Brand | Network |
| Mercedes-Benz | U030053 | Array output indicating Inverter Temperature Sensor Stuck in Range fault symptom status for each of the available inverter temperature sensors. Brand | Network |
| Mercedes-Benz | U030054 | An internal fault has occurred in the control unit software. Missing Calibration Brand | Network |
| Mercedes-Benz | U030055 | Array output indicating Inverter Temperature Sensor Circuit Short to Battery fault symptom status for each of the available inverter temperature sensors. Brand | Network |
| Volvo | U030055 | Check to see if diagnostic trouble code (DTC) FSM- is stored Brand | Network |
| Mercedes-Benz | U030056 | An internal fault has occurred in the control unit software. Invalid / Incompatible Configuration Brand | Network |
| Mercedes-Benz | U030057 | An internal fault has occurred in the control unit software. Invalid / Incompatible Software Component. Brand | Network |
| Mercedes-Benz | U030061 | ADC test command feedback voltage - Too Low Brand | Network |
| Mercedes-Benz | U030062 | ADC test command feedback voltage - Too High Brand | Network |
| Mercedes-Benz | U030064 | An internal fault has occurred in the control unit software. Signal Plausibility Failure. Brand | Network |
| Mercedes-Benz | U030068 | The DC Current sensor short to ground fault Brand | Network |
| Mercedes-Benz | U030071 | The DC Current sensor out of range low fault. Brand | Network |
| Mercedes-Benz | U030072 | The DC Current sensor offset out of range fault Brand | Network |
| Mercedes-Benz | U030073 | 15V HV Voltage - Too Low Brand | Network |
| Mercedes-Benz | U030074 | 15V LV Voltage - Too High Brand | Network |
| Mercedes-Benz | U030092 | An internal fault has occurred in the control unit software. Performance or Incorrect Operation Brand | Network |
| Mercedes-Benz | U030093 | Pump1 Motor Bridge Sensot Temp -Too high Brand | Network |
| Mercedes-Benz | U030094 | Pump2 Motor Bridge Sensor Temp -Too high Brand | Network |
| Mercedes-Benz | U030097 | An internal fault has occurred in the control unit software. Component or System Operation Obstructed or Blocked. Brand | Network |
| Mercedes-Benz | U03009A | An internal fault has occurred in the control unit software. Component or System Operating Conditions. Brand | Network |
| Mercedes-Benz | U0300E0 | An internal fault has occurred in the control unit software. Brand | Network |
| Mercedes-Benz | U0300E1 | In einem der Signale IPC_M_HMHQ_EHR_EI_CUM_SQC_POM, IPC_M_HMHQ_EHR_EI_CUM_CRC_POM, IPC_M_HMHQ_EHR_EI_CUM_SQC_PRF, IPC_M_HMHQ_EHR_EI_CUM_CRC_PRF wird ein Fehler angezeigt Brand | Network |
| Mercedes-Benz | U0300E2 | An internal fault has occurred in the control unit software. Brand | Network |
| Mercedes-Benz | U0300E3 | No description available | Network |
| Mercedes-Benz | U0300E4 | An internal fault has occurred in the control unit software. S/W modules on QNX reported errors in SLog2 with verbosity 'ERROR' Brand | Network |
| Mercedes-Benz | U0300E5 | An internal fault has occurred in the control unit software. S/W modules on QNX reported errors in SLog2 with verbosity 'CRITICAL' Brand | Network |
| Mercedes-Benz | U0300E6 | Error related to Exception that occured Brand | Network |
| Mercedes-Benz | U0300E7 | An internal fault has occurred in the control unit software. Error during mP shut-off path test Brand | Network |
| Mercedes-Benz | U0300E8 | Added for future purpose Brand | Network |
| Mercedes-Benz | U0300E9 | An internal fault has occurred in the control unit software. Error during the state change Brand | Network |
| Mercedes-Benz | U0300EA | An internal fault has occurred in the control unit software. Errors related to mP Floating Point Exception Monitoring Brand | Network |
| Mercedes-Benz | U0300EB | A failure in internal software communication occurred. Brand | Network |
| Mercedes-Benz | U0300EC | Das Signal MIC_AirTemp_SWM zeigt einen Fehler an Brand | Network |
| Mercedes-Benz | U0300ED | Das Signale DLB_EI_MIC_DLB_Stat zeigt einen Fehler an Brand | Network |
| Mercedes-Benz | U0300EE | Das Signal DSM_EI_MIC_FtWhlAngl zeigt einen Fehler an Brand | Network |
| Mercedes-Benz | U0300EF | Das Signal DSM_EI_MIC_LngVehVel zeigt einen Fehler an Brand | Network |
| Mercedes-Benz | U0300FA | Operating system time overrun error Brand | Network |
| Mercedes-Benz | U0300FB | Operating system stack overrun error Brand | Network |
| Mercedes-Benz | U0300FC | Multiple task activation Brand | Network |
| Mercedes-Benz | U0300FD | OS access violation Brand | Network |
| Mercedes-Benz | U0300FE | Task ID is not a valid task type Brand | Network |
| Mercedes-Benz | U0300FF | Calling task still holds resources. Brand | Network |
6Related codes
Browse Uxxx codes or U030xx codes.