Colleagues,

Driving the 99 740iL and the brakes begin to come on--probably first the left rear, and the pressure applied to the brakes builds up until the DSC, and ABS lights come on (BRAKE light always on, don't know why), and the car comes to a stop.

Tried SDMike's technique of putting cold packs on the DSC control unit, waiting 15-30 min, and thought it worked, on restart DSC and ABS go off, and it felt like there was no brakes being applied but the brake "pressure buildup" repeated after only a mile.

It appears that after a certain amount of time waiting (15-30 min), the pressure equalizes, or something else happens, and on restart DSC and ABS go off, although the second time, even after almost an hour, on restart DSC and ABS are off, but as soon as you touch the brake pedal to shift into drive, DSC and ABS come on, and brakes are on hard.

What is most likely
--debris in one of the caliper pistons,
--faulty pressure sensor
--faulty ASC Hydro unit (or pre-booster pump)
--debris in Hydro unit or pre-booster pump
--faulty DSC control unit

I'm asking for advice on where to look first, not remote divination of reality. Thanks in advance for your help

Craig