Autonomous vehicle failure mode management

1. A system, comprising:

a vehicle computer and a remote server,

wherein the vehicle computer is programmed to:

determine a first risk level for operating a vehicle based on (1) a trouble code indicating a failure of a specified vehicle electronic control unit or sensor and (2) stored data specifying the first risk level for the failure of the specified vehicle electronic control unit or sensor;

transmit the first risk level to a remote server;

then, after transmitting the first risk level, receive, from the remote server, an instruction to take an action; and

operate the vehicle to take the action; and

wherein the remote server is programmed to:

receive the first risk level from the vehicle computer;

based on the first risk level and additional data that includes a stored weight that is applied to the additional data, determine a second risk level for the failure of the specified vehicle electronic control unit or sensor;

based on the second risk level, determine an action for the vehicle; and

transmit the action to the vehicle computer.

2. The system of claim 1 , wherein the vehicle computer is further programmed to:

halt the vehicle based on determining that the initial risk level of the failure is greater than a threshold; and

begin to move the vehicle again based on the action in the instruction from the remote server.

3. The system of claim 1 , wherein the action includes operating by revising a route to a destination based on determining that revising the route reduces the second risk level with respect to the first risk level.

4. The system of claim 1 , wherein the second risk level is based on first weather data along an original route and second weather data along a revised route.

5. The system of claim 1 , wherein the additional data is received from a source different than the vehicle computer or the remote server.

6. The system of claim 1 , wherein the vehicle computer is further programmed to:

determine, that within a time period specified for transmitting the initial data to the remote server, that the vehicle computer did not receive a response from the remote server; and

halt the vehicle based on determining that the vehicle computer did not receive the response.

7. The system of claim 1 , wherein the additional data includes data indicating a back-up system on the vehicle that can replace some of the functionality of the failure; and the revised risk level is based in part on the data indicating the back-up system.

8. The system of claim 7 , wherein the additional data includes a reliability of the back-up system.

9. The system of claim 1 , wherein the additional data includes data from other vehicles of a same type, and the revised risk level is based in part on the data from the other vehicles of the same type.

10. A method comprising:

determining a first risk level for operating a vehicle based on (1) a trouble code indicating a failure of a specified vehicle electronic control unit or sensor and (2) stored data specifying the first risk level for the failure of the specified vehicle electronic control unit or sensor;

transmitting the first risk level from a vehicle computer to a remote server;

receiving the first risk level in the remote server;

based on the first risk level and additional data that includes a stored weight that is applied to the additional data, determining, in the remote server, a second risk level for the failure of the specified vehicle electronic control unit or sensor and, based on the second risk level, an action for the vehicle;

then transmitting an instruction including the action from the remote server to the vehicle computer

receiving, from the remote server, the instruction to take the action; and

operating the vehicle to take the action.

11. The method of claim 10 , further comprising:

halting the vehicle based on determining that the initial risk level of the failure is greater than a threshold; and

beginning to move the vehicle again based on the action in the instruction from the remote server.

12. The method of claim 10 , wherein the action includes operating by revising a route to a destination based on determining that revising the route reduces the second risk level with respect to the first risk level.

13. The method of claim 12 , wherein the second risk level is based on first weather data along an original route and second weather data along a revised route.

14. The method of claim 10 , further comprising:

determining, that within a time period specified for transmitting the initial data to the remote server, that the vehicle computer did not receive a response from the remote server; and

halting the vehicle based on determining that the vehicle computer did not receive the response.