Bmw 5 series abs light is on, changed the rr sensor which the computer indicted but still light on

SOURCE: BMW 2001 X5 has intermittent ABS light

BMW MODELS AFFECTED: All with ABS

FAULT: ABS warning light comes on intermittently. Normal troubleshooting procedures find no defect.

Possible Cause: If car has recently had two new tires, or snow tires put on. Sometimes when the car is driven over 50 MPH.

Solution: Check all four tires on the car, make sure they are the same brand, style, and size. Check if
any of the new tires have substantially more tread than the rest. These differences may cause enough
variance in rolling diameters to confuse the ABS control unit, which in turn, gives a false signal to the ABS
warning light.

If that is not the issue, it is most likely the ABS control module failing.

SOURCE: speedo and abs light on bmw 5 series

I've had the same problem twice on my 1999 528. The problem is your ABS module. (Bosch 5.7 to be exact.) The failure mode is temperature sensitive and shows up after driving. To test this, turn off the car, get a can of freeze spray and cool down the module. Inverting a can of compressed air used for computer cleaning works too. Give it a healthy freeze, then start up the car again. If the lights are out, then you know your problem. 
All sorts of things don't work when the module is bad. Speedo, windshield washers only give you one speed, fuel gauge drifts back and forth, cruise control,  check engine lights, airbag lights .... and so on, you get the picture, basically anything connected to the computer. My new (great) mechanic calls this the BMW christmas tree. 
You can either replace the module with a new one from the dealer, very expensive, or get it rebuilt. There are a number of rebuilders out there, so take your pick. I've used ModuleMaster in the past and they've been great. $300 and works like a charm. Google them to find their web site, and good luck. 
db

SOURCE: BMW 5 series - 2005 model - resetting service & waring lights

the brake pad warning light is controlled by a sensor located in the front and rear brake pads, small contact with 2 wires that plud into a harness, if they are bad I think the replacement cost is around 5-10 dollars for a new one, there will only be one in the front and one in the rear, the service light is turned out by a special tool at the dealer

SOURCE: bmw 520i 1999 abs/asc lights on diagnostic

Check to see if your brake pads and rotors are in good condition. Or if you have replaced the pads yourself and have not reset the wheel sensors this would cause the ABS Antilock Brake System light and the ASC Automatic Stability Control light to stay on as the ASC uses the ABS brakes with computer assistance to control the car

Mike Watson

• 474 Answers
• Posted on Mar 10, 2010

SOURCE: abs light on and the speedometer stop working on

Sorry I don't know much about BMW but I do know about cars and it sounds like you have a bad wheel speed sensor or more than one which controls those systems.If the car does not get a signal of how fast the wheel is spinning it will make the traction control not work along with the ABS.