NetworkU0301
SeriousSeverity: Serious - have it checked soon
Software incompatibility with ECM/PCM
Key terms: Control module: a small computer that runs one part of the car
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 25
| Brand | Code | Description | System |
|---|---|---|---|
| Ashok Leyland CV | U0301 | Evaporative Emission Control System Leak Detected (Fuel Tank Cap) Brand | Network |
| BAIC Motor | U0301 | Vehicle configuration error Brand | Network |
| BYD | U0301 | Software Incompatibility With ECM/PCM Brand | Network |
| Chery | U0301 | Software Incompatibility With ECM/PCM Brand | Network |
| Daewoo | U0301 | Software Incompatibility With ECM/PCM Brand | Network |
| DFFS | U0301 | Software Incompatibility With ECM/PCM Brand | Network |
| DFFX | U0301 | Software Incompatibility With ECM/PCM Brand | Network |
| DFXK | U0301 | Software Incompatibility With ECM/PCM Brand | Network |
| EOBD | U0301 | Tarkvara ühildamatus ECM/PCM-ga Brand | Network |
| Geely | U0301 | Vehicle configuration unmatched Brand | Network |
| GM | U0301 | Software Incompatibility With ECM/PCM Brand | Network |
| Great Wall | U0301 | Software Incompatibility With ECM/PCM Brand | Network |
| Hafei | U0301 | Software Incompatibility With ECM/PCM Brand | Network |
| Holden | U0301 | Software Incompatibility With Engine Control Module Brand | Network |
| Honda | U0301 | No description available | Network |
| Hyundai | U0301 | No description available | Network |
| Land Rover | U0301 | Software incompatibility with the powertrain control module Brand | Network |
| Opel | U0301 | Software Incompatibility With ECM/PCM Brand | Network |
| Peugeot | U0301 | No description available | Network |
| Proton | U0301 | No description available | Network |
| Saab | U0301 | Software Incompatibility With ECM/PCM Brand | Network |
| MG (SAIC) | U0301 | Software Incompatibility With ECM/PCM Brand | Network |
| Tata | U0301 | Software Incompatibility With ECM/PCM Brand | Network |
| Toyota | U0301 | Software incompatibility with ECM/PCM Brand | Network |
| Volkswagen | U0301 | Software incompatibility with engine control module; Defective 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 50
These 7-character codes are manufacturer-specific variants of U0301 and may be reported by some scan tools.
| Brand | Code | Description | System |
|---|---|---|---|
| Mercedes-Benz | U030102 | An internal fault has occurred in the control unit software. Brand | Network |
| Mercedes-Benz | U030103 | An internal fault has occurred in the control unit software. Brand | Network |
| Mercedes-Benz | U030104 | An internal fault has occurred in the control unit software. Brand | Network |
| Mercedes-Benz | U030105 | An internal fault has occurred in the control unit software. Brand | Network |
| Mercedes-Benz | U030106 | An internal fault has occurred in the control unit software. Brand | Network |
| Mercedes-Benz | U030107 | An internal fault has occurred in the control unit software. Brand | Network |
| Mercedes-Benz | U030108 | An internal fault has occurred in the control unit software. Brand | Network |
| Mercedes-Benz | U030109 | An internal fault has occurred in the control unit software. Brand | Network |
| Mercedes-Benz | U03010A | An internal fault has occurred in the control unit software. Brand | Network |
| Mercedes-Benz | U03010B | An internal fault has occurred in the control unit software. Brand | Network |
| Mercedes-Benz | U03010C | An internal fault has occurred in the control unit software. Brand | Network |
| Mercedes-Benz | U03010D | An internal fault has occurred in the control unit software. Brand | Network |
| Mercedes-Benz | U03010E | An internal fault has occurred in the control unit software. Brand | Network |
| Mercedes-Benz | U03010F | An internal fault has occurred in the control unit software. Brand | Network |
| Mercedes-Benz | U030110 | An internal fault has occurred in the control unit software. Brand | Network |
| Mercedes-Benz | U030111 | An internal fault has occurred in the control unit software. Brand | Network |
| Mercedes-Benz | U030112 | An internal fault has occurred in the control unit software. Brand | Network |
| Mercedes-Benz | U030113 | An internal fault has occurred in the control unit software. Brand | Network |
| Mercedes-Benz | U030114 | An internal fault has occurred in the control unit software. Brand | Network |
| Mercedes-Benz | U030115 | An internal fault has occurred in the control unit software. Brand | Network |
| Mercedes-Benz | U030116 | An internal fault has occurred in the control unit software. Brand | Network |
| Mercedes-Benz | U030117 | An internal fault has occurred in the control unit software. Brand | Network |
| Mercedes-Benz | U030118 | An internal fault has occurred in the control unit software. Brand | Network |
| Mercedes-Benz | U030119 | An internal fault has occurred in the control unit software. Brand | Network |
| Mercedes-Benz | U03011A | An internal fault has occurred in the control unit software. Brand | Network |
| Mercedes-Benz | U03011B | An internal fault has occurred in the control unit software. Brand | Network |
| Mercedes-Benz | U03011C | An internal fault has occurred in the control unit software. Brand | Network |
| Mercedes-Benz | U03011D | An internal fault has occurred in the control unit software. Brand | Network |
| Mercedes-Benz | U03011E | An internal fault has occurred in the control unit software. Brand | Network |
| Mercedes-Benz | U03011F | An internal fault has occurred in the control unit software. Brand | Network |
| Mercedes-Benz | U030120 | An internal fault has occurred in the control unit software. Brand | Network |
| Mercedes-Benz | U030121 | An internal fault has occurred in the control unit software. Brand | Network |
| Mercedes-Benz | U030122 | An internal fault has occurred in the control unit software. Brand | Network |
| Mercedes-Benz | U030123 | An internal fault has occurred in the control unit software. Brand | Network |
| Mercedes-Benz | U030124 | An internal fault has occurred in the control unit software. Brand | Network |
| Mercedes-Benz | U030125 | An internal fault has occurred in the control unit software. Brand | Network |
| Mercedes-Benz | U030126 | An internal fault has occurred in the control unit software. Brand | Network |
| Mercedes-Benz | U030127 | An internal fault has occurred in the control unit software. Brand | Network |
| Mercedes-Benz | U030128 | An internal fault has occurred in the control unit software. Brand | Network |
| Mercedes-Benz | U030129 | An internal fault has occurred in the control unit software. Brand | Network |
| Mercedes-Benz | U03012A | An internal fault has occurred in the control unit software. Brand | Network |
| Mercedes-Benz | U03012B | An internal fault has occurred in the control unit software. Brand | Network |
| Mercedes-Benz | U03012C | An internal fault has occurred in the control unit software. Brand | Network |
| Mercedes-Benz | U03012D | An internal fault has occurred in the control unit software. Brand | Network |
| Mercedes-Benz | U030130 | An internal fault has occurred in the control unit software. Brand | Network |
| Mercedes-Benz | U030141 | The DC Current sensor plausibility fault Brand | Network |
| Mercedes-Benz | U030142 | Array output indicating Inverter Temperature Sensor Out of Range Low fault symptom status for each of the available inverter temperature sensors. Brand | Network |
| Mercedes-Benz | U030143 | 5V Safety Current Sensing Feedback - Voltage to High Brand | Network |
| Mercedes-Benz | U030145 | Current Sensor C noisy Brand | Network |
| Mercedes-Benz | U030147 | No description available | Network |
6Related codes
Browse Uxxx codes or U030xx codes.