Evaluation Table for Sensor Test

Tested / Requirements

Information Fault / Fault Elimination

Installed position of sensors by way of the output voltage

Sensors receive an input voltage of 5 V from the ABS / PDAS control unit. Output voltage is 2.7 V insofar as the sensor is in horizontal position and in perfect condition.

Specifications:

2.7 ±0.14 volts for a stationary car on a level surface (ignition turned on).

Test value above or below specified value = bent sensor console or faulty sensor.

No voltage displayed = break in electric leads or faulty sensor. If applicable, check electric leads according to the wiring diagram. Certain faults (breaks / shorts / faulty sensor) are stored in the fault memory of the ABS/PDAS control unit. Consequently always read out and, if applicable, cancel the fault memory with a 9288 System Tester after elimination of faults (see page 39/45-1).

Sensor function / mix-up test

Test by lifting car approx. 150 mm each 1 x right front and 1 x left front.

This ust produce a precisely defined change in voltage. Use the above mentioned test (output voltage for a car on level surface) as a reference value.

Axial acceleration sensor

Specifications:

The output voltage must change in the direction of less voltage when lifting the car at right front and left front.

Example: Output voltage Left front lifted Right front lifted

Lateral acceleration sensor

Specifications:

With the output voltage value as a basis there must be greater voltage when lifting at left front and less voltage when lifting at right front.

Example: Output voltage Left front lifted Right front lifted

Tested / Information

Requirements

Fault / Fault Elimination

Always check the symbols (identification for axial acceleration sensor and lateral acceleration sensor) on the adapter plug (mix-up test).

Electric lead plugs are mixed up on the sensors, if the voltage changes in direction of more and in direction of less voltage (as should be on the lateral acceleration sensor) when testing the axial acceleration sensor (lifted 1 x left and 1 x right). See page 45 -1 for cross reference.

The pertinent sensor has a fault, if there is no change in voltage while lifting (left and right lifted the same distance). Eliminate the fault and then read out and, if applicable, cancel the fault memory with a 9288 System Tester.

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