My 2001 740I has the ABS, Brake and Traction warning lights up. it just happened today. Braking and steering feels normal.
ABS, Brake and Traction warning lights on 2001 BMW 740i
Same thing happened to mine a couple of weeks ago - it ended up being the right rear wheel speed sensor. If you have an AutoZone in your area, they can plug in and tell you which wheel is bad (each wheel has it's own sensor). The part will run you $145.00 online - it's an easy DIY repair. You'll need a #8 metric hex bit and about 1/2 hour. Once you replace the sensor and plug it in, the fault will self correct and the lights will go out.
You'll want to get the codes in the ABS Module checked to see why the light is coming on. Many vehicles have issues with the modules, so much so there are companies that rebuild them for you, have a look at this site for more info.