Yellow brake lights and DSC lights are on at the same time on the dash. What does that mean?

it could be worn brakes for the red dash brake light if you mean the cars rear brake lights in the back of the car won't turn off the brake light switch at the brake pedal has shorted out making them stay on also you say the abs light is on there could be an issue with the brakes/sensors/air in the system if both dash lights are on the red one and the yellow one

It's an yellow warning indicator lamp. It lights when front brake pads are weared. Now it's time to replace used brake pads!

It's an yellow warning indicator lamp. It lights when brake pads are weared. Now it's time to replace the used brake pads!

It's an yellow warning indicator lamp. It lights when brake pads are weared. Now it's time to replace used brake pads!

The vehicle owner's manual will contain that information.

Check the level of a brake fluid.If low-check the condition of the brake pads.If nessecary-change them.

Check your air pressure in your tires.

IF dsc is on all the time you probably have a problem with a wheel sensor (or its cabling/plug) or dsc controller, also check brake fluid level.
good luck.

Abs and dsc are related and with the light on these won't work. It is possible that you need to go back to where the work was done to look this over.

sounds like your brake lining light. It means your brakes have worn below specification. The light to me kinda looks like a yellow circle with two dashes on one side and two on the other and they follow the curvature of the circle. On an x3 you can get a pretty good view of the brake pads looking through the wheel.