Instruction Manual

Maintenance
16 (26) © Nokia Corporation DN00283717
Nokia Proprietary and Confidential Issue 2 DRAFT 1 - en
3. Go to the Local Unit window of the ISMMan software. Use the ISMMan
software to switch off the DL laser of the relevant LU. The colour of the
LED icon will change to red.
4. Remove the four M3 x 20 fixing screws that secure the cable cover to the
Remote Unit mounting rack.
5. Remove the cable cover.
6. Disconnect the power supply cable from the RU.
7. Disconnect the antenna cables from the RU.
8. Disconnect carefully the two fibre optic cables from the RU and fit
protective caps to the ends of the fibre optic cables.
9. Remove the five M3 x 8 fixing screws that secure the RU to its mounting
rack.
10. Lift the RU up and off its mounting rack, then store in a safe place.
11. Obtain a known good RU and carefully place it on the mounting rack,
pushing it down gently to secure it in position.
12. Secure the RU to the mounting rack using five fixing screws.
13. Connect the antenna cables to the RU in their correct positions.
14. Remove the protective caps from the ends of the fibre optic cables and
connect carefully the two fibre optic cables to the RU. Store the protective
caps in a safe place.
15. Secure the cable cover of the RU mounting rack with four screws.
16. Connect the power supply cable to the RU power supply connector.
17. Where applicable, set the RU power to ON at the mains switchboard or at
the CPSU or insert power supply plug to the socket.
18. At the location of the replacement RU, verify that its power LED is lit
(green) and the red FAULT LED is unlit (dark) on the RU.
19. Use the supervisor software to check that the alarm has disappeared.
20. Send the faulty RU, suitably identified and fault symptom(s) stated, to
Nokia for repair, using the procedure advised by the local Nokia agent.