I have a 2003 Cooper with ABS and flat tire warning lights on and I used the following procedure to fix the problem.


1. Disconnect large multiple-wire connector leading to the ABS control module under the hood on the firewall at the passenger side by pulling up on the plastic tab.
2. Then use a thin probe connected to a multimeter to measure the resistance of the 4 pairs of wires that lead to the ABS sensors at the wheels.

Left front wheel: connectors 45 and 46. Brown/red and brown wires.
Right front: connectors 33,34. Brown and yellow wires
Left rear: connectors 36,37. Blue and brown
Right rear: connectors 42,43. Yellow/black and yellow/brown


Each pair should read approximately 19 mega ohms. I got 19 at three of the wheels and “O.L”. at connectors 45-46. So I replaced the left front wheel sensor and the warning lights went off. I paid $55 for the sensor and prices online range from about $15 to $120 depending on the brand.