Patent ID: 7595720

Claim:
A tester for testing an active wheel speed sensor of a vehicle, comprising: an indication portion having a plurality of indicators; a module testing portion configured to assess operation of a system control module of the vehicle by monitoring an electrical output from the system control module to cause indication of proper operation of the system control module with a first indicator of the plurality of indicators, and to identify whether further testing of operation of the active wheel speed sensor is needed; a sensor testing portion configured to assess operation of the active wheel speed sensor and to cause indication of proper operation with a second indicator of the plurality of indicators; and a tester connector provided on the tester, the tester connector being configured to connect to a connection harness that is detachably connectable to the vehicle, to electrically connect the tester to the system control module and the active wheel speed sensor in situ in the vehicle, at the same time or independently, via a respective sensor connector and a module connector of the detachable connection harness; wherein the indication portion is electrically communicated to an electronic circuit of the module testing portion and an electronic circuit of the sensor testing portion and the first indicator and the second indicator are LEDs; wherein the electronic circuit of the sensor testing portion detects if a current in the active wheel speed sensor is in a predetermined range, a predetermined high current state, or a predetermined low current state, and is configured to light a current level LED if the current is outside the predetermined range, and to light a high current state LED if the current is in the predetermined high current state, and to light a low current state LED if the current is in the predetermined low current state; and wherein proper function of the active wheel speed sensor is indicated by blink of the lighting of the high current state LED and the low current state LED while a wheel is turned.