WIS Document: 4028

| | LED Fault symptom LED does not light Diagnostic procedure 1 Check the operation of the LED | - | Connect the ISAT scan tool. | - | Select "ACTIVATE". | - | Select "LED". | - | Select "ON". The LED should light up. Is the LED on? | yes The fault is of intermittent nature, proceed to point 6. | no Continue with point 2. 2 Check the operation of the LED (contd.) | - | Unplug the LED. | - | Connect the test lamp to the 2-pin LED connector. | - | Repeat the ISAT scan tool command as in point 1. The test lamp should light. Is the test lamp on? | yes Change the LED. | no Continue with point 3. 3 Check the LED's power supply | - | Unplug connector H33-1. | - | Connect the test lamp to pin 29 of connector H33-1 and a good grounding point. | - | Repeat the ISAT scan tool command as in point 1. The test lamp should light. Is the test lamp on? | yes Continue with point 4. | no Continue with point 5. 4 Check the LED wiring Conduct a continuity test on the cable assembly between | - | connector H33-1, pin 29, and the 2-pin LED connector, pin 2. | - | the 2-pin LED connector, pin 1, and grounding point G34S. The resistance should be < 1 ohm. Is the resistance correct? | yes Continue with point 6. | no Repair or replace the wiring harness. 5 Check the wiring connected to the electronic control module Conduct a continuity test on the cable assembly between connector H33-1, pin 29 and the control module, pin 2. The resistance should be < 1 ohm. Is the resistance correct? | yes Continue with point 6. | no Repair or replace the wiring harness. 6 Final check Check to see if the fault symptom remains. Is the problem still present? | yes See "Before replacing a control module". | no The remedial measures taken were correct or the fault is of intermittent nature.