2401054 - 5040CD Check on climate control fan' speed control signal

With the Examiner set to voltmeter function, select 20 volts full scale deflection and time base 5 seconds.Connect the black probe of the Examiner to the vehicle earth and the red probe to pin 2 of the speed regulator connectorTurn the ignition ON.Press the START button.The signal displayed must be a PWM pulse train with a Duty Cycle that varies as shown in the graph Check that an earth signal is present on pin 3 of the regulatorCheck that a PWM signal is present at pin 1 (diagnostic signal)Check that the motor is correctly supplied via the regulator with a voltage signal at pins 5 and 6 as shown in the attached graph.