Method for monitoring a brake system with at least one brake actuator of a brake arrangement having a plurality of brake systems of a rail vehicle, wherein • a deceleration of the rail vehicle is detected by obtaining a deceleration measured variable, and • a deceleration difference actual value (Δd act ) is formed from a measured deceleration actual value (d act ) and a predefined deceleration setpoint value (d setp ) as a deceleration measured variable, characterized in that • the deceleration difference actual value (Δd act ) is compared with a deceleration difference threshold value (Δd setp ) by forming a deceleration difference intermediate value (Δd int ), and in the case of a deceleration difference intermediate value (Δd int ) which is above a tolerance value, a deceleration defect signal (LD) is generated, which is supplied to an AND element , • a braking force (f) of the at least one brake actuator is measured, • a force difference actual value (Δf act ) is formed from a measured force actual value (f act ) and a predefined force setpoint value (f setp ), • the force difference actual value (Δf act ) is compared with a force difference threshold value (Δf setp ) by forming a force difference intermediate value (Δf int ), and in the case of a force difference intermediate value (Δf int ) which is above a tolerance value, a force defect signal (LF) is generated, which is fed to the AND element , and • an error message signal (BF) is generated from the deceleration defect signal (LD) and force defect signal (LF) which are fed to the AND element , • wherein a speed actual value (v act ) of the rail vehicle is compared with a speed limiting value (v limit ), and in the case of a speed actual value (v act ) which is below the speed limiting value (v limit ), the formation of the error message signal (BF) is blocked. • a deceleration of the rail vehicle is detected by obtaining a deceleration measured variable, and • a deceleration difference actual value (Δd act ) is formed from a measured deceleration actual value (d act ) and a predefined deceleration setpoint value (d setp ) as a deceleration measured variable, characterized in that • the deceleration difference actual value (Δd act ) is compared with a deceleration difference threshold value (Δd setp ) by forming a deceleration difference intermediate value (Δd int ), and in the case of a deceleration difference intermediate value (Δd int ) which is above a tolerance value, a deceleration defect signal (LD) is generated, which is supplied to an AND element , • a braking force (f) of the at least one brake actuator is measured, • a force difference actual value (Δf act ) is formed from a measured force actual value (f act ) and a predefined force setpoint value (f setp ), • the force difference actual value (Δf act ) is compared with a force difference threshold value (Δf setp ) by forming a force difference intermediate value (Δf int ), and in the case of a force difference intermediate value (Δf int ) which is above a tolerance value, a force defect signal (LF) is generated, which is fed to the AND element , and • an error message signal (BF) is generated from the deceleration defect signal (LD) and force defect signal (LF) which are fed to the AND element , • wherein a speed actual value (v act ) of the rail vehicle is compared with a speed limiting value (v limit ), and in the case of a speed actual value (v act ) which is below the speed limiting value (v limit ), the formation of the error message signal (BF) is blocked. <EOS>