A. Model 129

1. Remove left trunk panel and taillamp assembly.

2. Connect harness to relay box and secure with thumb screws.

3. Install two clip nuts onto relay box bracket.

4. Attach foam padding to concave portion of bracket.





5. Clamp relay box to left frame with bracket and two sheet metal screws (Fig. 17).

6. Connect harness connections to sound system control unit as follows:

Line-out connections
a. disconnect 3-pole female and 1-pole ground connectors from line-out unit on tuner/amplifier.
b. connect 3-pole female and 1-pole ground connectors from relay box to line out unit on tuner/amplifier.
c. connect 3-pole male and 1-pole ground connectors from relay box to 3-pole female and 1-pole ground from step 6a.

Left speaker connections
d. disconnect white male speaker connector (left channel) from tuner/amplifier.
e. connect white male speaker connector from relay box to tuner/amplifier.
f. connect white female speaker connector from relay box to white male speaker connector from step 6d.

Control connections
g. disconnect 1/4" female lug from tuner/amplifier.
h. connect 1/4" female lug from relay box to tuner/amplifier.
i. connect 1/4" male lug from relay box to 1/4" female lug from step 6g.





7. Assemble transmitter - receiver to mounting plate using brackets (one on each end of transmitter - receiver, Fig. 18).

8. Attach pig-tail junction box to plate, secure with cable tie (Fig. 18).

9. Connect cable from junction box to transmitter - receiver.

10. Remove protective caps from studs in bottom of wheel well.

11. Partially remove carpeting from left trunk area.

12. Install clips to longitudinal rail over existing holes. Replace carpeting.

13. Position transmitter - receiver mounting plate over studs in wheel well. Insert sheet metal screws through holes in transmitter - receiver plate into clips, do not tighten. Place nuts on studs and tighten. Tighten sheet metal screws.

14. Connect white 4-pole connector (power supply) to transmitter - receiver.





Note:
On vehicles built up to early December production, check for proper pin layout of the white 4-pole harness connector. If pin layout is incorrect, place wires/pins in proper locations in connector.

15. Connect black male speaker connector from relay box to black female speaker connector in telephone harness.

16. Connect 3-pole male connector from relay box to 3-pole female connector in telephone harness. Do not confuse this connector with the 3-pole line-out connector.

17. Disconnect the radio antenna lead from antenna splitter. Check for continuity from the antenna mast tube to vehicle chassis with an Ohmmeter. If the nominal value is [greater than] 0.3 Ohm , loosen the lower antenna mounting screw and then tighten the mast tube nut until value is [less than or equal to] 0.3 Ohm. Tighten lower mounting screw. Reconnect radio antenna lead to splitter.

Note:
Failure to perform this step will lead to poor telephone performance and/or interference to other vehicle electronic systems.

18. Connect 1-pole female telephone harness connector to antenna (behind 4-pole connector).

19. Connect black telephone harness data cable to junction box on transmitter - receiver plate.

20. Connect one end of the antenna lead cable to the transmitter - receiver, the other end to the "Telefon connection on the splitter box.





21. Secure loose wires, cables with cable tie (Fig. 19).

22. Reinstall left wheel well liner and taillamp assembly.





23. Install 8 A fuse in auxiliary fuse box (located in trunk, above battery, Fig. 20).

Note:
In some early production 129 vehicles, the auxiliary fuse box was not installed. For subsequent installation, plug fuse box (201 540 03 50) into socket in trunk above battery. Install 8A fuse in left holder and close with cover (123 545 04 46).

24. Reconnect negative battery terminal.

25. Program telephone.

Note:
On Model 600 SL, Option Bit programming (step 8) is already performed at VPC. Follow instructions for Subsequent NAM programming.

26. Recode radio.

27. Test function.