Specifications

Chapter 6: FRU Replacement and Fault Isolation Procedures

6-52

6.3.7 Exit Sensor failure continued

4. EXIT SENSOR ACTUATOR SIGNAL ANALYSIS

Disconnect P/J 111 from the HVPS. Perform this test within 30 seconds after switching power on.

After 30 seconds, the LVPS shuts down with a no-load condition.

Block the Sensor window with a piece of paper.

Is there +5VDC between P/J 16–3 and P/J 16–2 on the MCU PWB?

Remove the piece of paper from the Sensor window.

Is there 0VDC between P/J 16–3 and P/J16–2 on the MCU PWB?

Yes No

Replace the MCU PWB. Go to Step 5.

5. SENSOR HARNESS ASSEMBLY ANALYSIS

Disconnect J16 on the MCU PWB and J119 on the Exit Sensor.

Is there continuity (0Ω) between all wires on J16 and J119?

Yes No

Replace the Exit Sensor. Replace the Sensor Harness Assembly.