Page 20 - KNORR Pneumatic Disc Brake

5

Functional and Visual Check

Wear Indicators
5.1.8. Due to different vehicle manufacturers and vehi-
cles there are several types of pad wear indicator used.

a) In-pad normally closed indicator - circuit is broken
when pad wear reaches limit (see Fig.).
b) In-pad normally open indicator - circuit is made when
pad wear reaches limit (see Fig.).

c) Wear indicator using built-in potentiometer. This is avail-
able either as an on/off version or as a continuous signal
version which can be linked to the vehicle’s electronic
monitoring systems (see Fig.). 5.1.8a - 5.1.8b - In-pad wear Indicator

Either acoustic or optical diagnostic units can be
connected.

Note: Please also refer to specifications provided by the
vehicle manufacturer.

5.1.8c - Wear Indicator with built-in potentiometer

Knorr-Bremse diagnostic unit K154433N50
The Knorr-Bremse Potentiometer Tester serves;
- To test the Potentiometer function on
Knorr-Bremse disc brakes

- To check the wear condition of the brake pads
and brake discs

5.1.9. The Tester can be used on all current Knorr-Bremse
brake types with continues or black/white Potentiometer.

Note: Knorr-Bremse recommends that before replacing a
brake caliper with a suspected potentiometer failure, that it first
be tested using the Potentiometer Tester. If no defect is found,
the cause is not with the brake caliper and therefore does not
need replacing.

5.1.9 - Knorr-Bremse diagnostic unit K154433N50

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