U0146: Lost communication with gateway A
The network is not receiving messages from the gateway, the module that links the car’s different networks. Many faults tend to appear at once.
| Code | U0146 |
|---|---|
| System | Communication network |
| Group | U01xx, Lost communication with control units |
| Type | Generic: it means the same on every make |
| Can you keep driving? | With care |
What U0146 means
Modern cars have several data networks (engine, chassis, comfort, infotainment) and the gateway acts as the bridge between them, and often with the diagnostic socket too. This code means it has stopped responding. Because everything passes through it, it is normal to see many other codes and warnings at the same time.
Most common causes
- Low or flat battery, very common after the car has stood unused for a long time
- Blown gateway fuse
- Loose, corroded or damp gateway connector
- Poor ground on the gateway
- A faulty module jamming one of the networks
- Faulty gateway
Symptoms
- Many warning lights and messages at once
- Instrument cluster glitching or dead
- Reader cannot connect to some control units
- Unrelated functions stop working
- On some cars, no start
Can you drive with U0146?
With care Depending on which networks are cut off, the car may drive almost normally or show many faults. If brake, steering or engine warnings are on, do not take chances and get it to a garage promptly.
Open the bonnetthe in-depth explanation
How to check it
Charge the battery or check its voltage first; the fault often clears. Then clear the codes and see which return: if they all come back, the garage will need to inspect the gateway and its connections.
How to read and clear U0146 with Final OBD
Plug an OBD2 scanner in under the steering wheel, switch the ignition on and open Final OBD. Under Faults you’ll see U0146 with its description and whether it’s confirmed, pending or permanent.
If the engine stores it over standard OBD, with FREE you read this code with its explanation for nothing and clear it. With PRO you also read the faults of every control unit and clear them in all of them.
Clearing the code only turns the light off: if the cause is still there, it comes back. Clear it once it’s fixed, and not right before an inspection. It’s all in how to read and clear fault codes and in inspections and OBD.
Similar codes
- U0142 The body control unit B is not answering on the car network
- U0143 The body control unit C is not answering on the car network
- U0144 The body control unit D is not answering on the car network
- U0145 The body control unit E is not answering on the car network
- U0147 The gateway B is not answering on the car network
- U0148 The gateway C is not answering on the car network
- U0149 The gateway D is not answering on the car network
- U014A The battery energy control unit C is not answering on the car network
- U0100 Lost communication with engine control module (ECM/PCM A)
- U0101 Lost communication with transmission control module (TCM)
- U0102 Lost communication with transfer case control module
- U0103 Lost communication with the gear shift module
What does code U0146 mean?
Modern cars have several data networks (engine, chassis, comfort, infotainment) and the gateway acts as the bridge between them, and often with the diagnostic socket too. This code means it has stopped responding. Because everything passes through it, it is normal to see many other codes and warnings at the same time.
Can you drive with U0146?
Depending on which networks are cut off, the car may drive almost normally or show many faults. If brake, steering or engine warnings are on, do not take chances and get it to a garage promptly.
How do you clear U0146?
With an OBD2 scanner and an app like Final OBD, which clears it for free if it’s stored by the engine control unit. But clearing it only turns the light off: if the cause isn’t fixed, U0146 comes back.
Read it on your car
Final OBD reads and clears engine faults through standard OBD for free, each one explained in plain English. With PRO it also reads the faults of every control unit, each make’s own codes included, and clears them in all of them.
