Symptom
Probable cause
Repairs
Low pedal after
system bleeding
Master cylinder faulty Replace master cylinder.
Pedal spongy or
brakes work only
when pedal is
pumped
Air in brake fluid
Bleed system using factory or compatible
diagnostic tool
Master cylinder or
electronic control
system faulty
Replace master cylinder. Diagnose system using
factory or compatible diagnostic tool.
Excessive braking
effort
Brake pads wet
Use light pedal pressure to dry pads while
driving.
Brake pads
heat-glazed or fluid-
soaked
Replace brake pads and rotors. Replace leaking
calipers.
Vacuum booster or
vacuum hose
connections to
booster faulty
Inspect vacuum lines. Test vacuum booster and
replace as required. Test vacuum non-return
valve for one-way flow.
Brakes pulsate,
chatter or grab
Warped brake rotors
Resurface or replace rotors.
Brake pads worn
Replace brake pads.
Brake pads
heat-glazed or
oil-soaked
Replace brake pads. Clean rotors. Replace
leaking calipers.
Uneven braking,
car pulls to one
side, rear brakes
lock
Incorrect tire
pressures or worn
tires
Inspect tire condition. Check and correct tire
pressures.
Brake pads on one
side of car
heat-glazed or fluid-
soaked
Replace brake pads. Clean rotors. Replace
leaking calipers. .
Caliper or brake pads
binding
Clean and recondition brakes.
Worn suspension
components
Inspect for worn or damaged suspension
components. See
310 Front Suspension
or
330 Rear Suspension
.
Brakes drag, bind
or overheat
Brake caliper or
brake pads binding
Clean or replace caliper.
Master cylinder or
electronic control
system faulty
Replace master cylinder. Diagnose electronic
control system using factory or compatible
diagnostic tool.
Brakes
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Summary of Contents for 1999-2005 M3
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