Mercedes-Benz 124 1994 Operating and installation instructions

Mercedes-Benz service information
TO:OUR MERCEDES-BENZ PASSENGER CAR DEALERS
DATE: . November 1993 (supersedes S.I. MBNA 82/70, Aug.1993)REF. NO. MBNA 82/70a
Revision: to W.I. 302a andnew W.l.'s 303and304for models 124and202 respectively
SUBJECT:MODELS124,129, 140AND202
M.Y. 1994
INSTALLATION OF CELLULAR TELEPHONESYSTEM
Attached to this Service Information are Work Instructions for installation ofthe cellular telephonesystem
in model124,129, 140and202 modelyear1994 vehicles.
NAM Programming Guide S-2503-093 is valid for M.Y.1994model129, 140 vehicles (withcore kitQ6
82 0140).
NAM ProgrammingGuideS-2499-A92 is valid for models124,201,202.
©1993
Mercedes-Benz of NorthAmerica,Inc. Allrights reserved. Reproduction or translation in
Mercedes-Benz Canada,Inc.whole orin part isnot permittedwithoutauthorization
Service and PartsLiterature from the publisher.Printed in U.S.A.

Mercedes-Benz Service
Group: 82
Work Instructions Date: November1993 Number: 302a
SUBJECT: MODELS 129AND140
M.Y.1994
INSTALLATION OF CELLULARTELEPHONESYSTEM
INSTALLINGIN-DASHCONTROLLER(IDC)
1. Unpackcontents of installation kitand compare to parts list atendof work instructions. Readthrough
entire workinstructionprocedure to familiarize yourselfwithsequence of instructions and parts.
Remove OperatingGuidefrom kitand place in Owner'sLiteraturepouch.
2. Disconnect and covernegativebatteryterminal.
3. Examine inside of eyeglass compartment for presence ofa non-lined plastic "false back".
FOR EYEGLASSCOMPARTMENT WITH FALSE BACK (Steps4-9)
4.If falseback is installed,removal ofthe eyeglasscompartment isnot necessary.
5. Remove two screws securing false back to eyeglass compartment. Removefalseback to expose two
12-poleconnectors andone microphoneconnector.Removecables from falseback.Falseback and
original mountingscrews maybe discarded.
6. Install IDC mountingbracket. Position mountingbracket so thatmountingholesalignwithfalseback
mountingholes.Securebracket with four4x10 mm selftappingscrews.
7. Attach two self-adhesiveretainer clips to rear of
in-dashcontrollerwith the open end facing up
(Figure 1).
8. Connect two 12-po|econnectors to in-dash
controller. Connectmicrophoneconnector to
connection ontop center of controller.
Figure 1
©1991Mercedes-Benz of NorthAmerica,Inc. All rightsreserved.Reproduction or translation in whole
Mercedes-Benz Canada, Inc. orin part isnot permittedwithoutauthorization from the
Service and PartsLiteraturepublisher.Printed in U.S.A.

2
9. Secureleftcable and microphonecable to clips
on back of IDC.Slidein-dashcontrollerinto
bracket and snap intoplace - DONOT PRESS
ONTHELCD DISPLAY.
Figure 2
FOR EYEGLASSCOMPARTMENTWITHOUT FALSE BACK (Steps 10- 20)
10. If false back isnot installed, removeeyeglasscompartment(SMS,Body-assemblyjobs, Jobno.
68-155).
Note:Removelockcylinder to avoid damagingdashboardcovering.
11. Carefully cutoutthe recessedopening onthe
back oftheeye glasscompartment(Arrow,
Figure 3).Use cautionwhencutting soasnot
to damage the compartmentliner. Cut liner
insidecompartmentwith utility knife.File down
any sharpplasticedges.
Figure 3
W.I. 302a,Grp. 82

3
12. Place template (a)ontopof eyeglass
compartment (Figure 4).
13. Locate, punch and drill 5 mm holes according to
template.
14. Countersink holes by hand using 8.5mm drill
bit.
Figure 4
15. Place controller bracket in eyeglass
compartment. Insert two flat head screws
through topof eyeglass compartment, finger
tighten square nuts.
Figure 5
16. Slide in-dash controller into bracket and snap
into place - DONOT PRESS ONTHELCD
DISPLAY. Center controller and then tighten
two flat head screws.
17. Insert removal tool (b) into two slots ontopof
IDC, push down onthetopofthe tool and then
pull on tool to remove IDC.
Figure 6
W.I. 302a, Grp. 82

4
18. Attach two self-adhesive retainer clips to rear of
IDC with the open endofthe clips facing up.
19. Guide wires forIDC through round opening in
back ofthe eyeglass compartment.
Note: Model 140 Only
Guide two in-dash controller cables and microphone
cable tothetop right inside ofthe eyeglass
compartment. Secure cables totop right inside
corner of compartment opening using metal clip,
slide clip toward youto engage.
Figure 7
20. Reinstall eyeglass compartment with controller
bracket. Remove protective covers from ends
of controller cables and attach to in-dash
controller. Secure left cable and microphone
cable to clips on back of IDC. Slide IDC into
bracket and snap into place - DONOT PRESS
ON THELCD DISPLAY.
Figure 8

5
INSTALLING HANDSET (HS)
A. Model 129
B. Model 140
A. Model 129
1. Remove carpeting from center console.
2.Cutand remove styrofoam, uptothe horizontal
chamfer (arrows, Figure 9), from underside of
carpeting. Remove material from lip around the
underside of carpeting so reinforcing plate can
sit flat.
3. Place reinforcing plate on back of carpeting
(Figure 9).
4. Locate, punch and drill four inner holes to5 mm
5. Insert four screws through reinforcing plate and
carpeting. Mount cradle on carpeting and
secure screws.
Figure 9
6. Drill outer holes through carpeting to match the
diameter ofthe mounting plate holes.
7. Remove two forward screws in center console
compartment.
8. Place angular cradle bracket in console with
raised edge of bracket pointing towards the rear
of the compartment (Figure 10). Secure
bracket using thetwo removed screws.
Figure 10
W.I. 302a. Grp. 82

6
9. Replace carpeting and cradle into center
console compartment. Harness cord should be
routed onthe right side with cord taped to
chamfers on underside of carpeting. Secure
carpeting with two screws'(arrow, Figure 11)to
angle bracket in compartment.
10. Connect harness connector tothe right side
cradle connection andthe handset connector to
the left side (Figure 11). Place handset in
cradle.
Figure 11
B. Model 140
1. Open armrest and place cradle inside
compartment. The front edge ofthe cradle
must touch the front wall ofthe armrest, and
thetwo holes inthe cradle must be centered
over the small pre-punched holes inthe armrest
floor (use a good shoplight to locate holes).
Figure 12
2. Attach coil cord retaining spring to notches on
underside of cradle.
3. Attach cradle and cord spring to armrest using
two M4x14 pan head tapping screws. Cover
screws with rubber caps with white stripe facing
downward.
Figure 13
W.I. 302a, Grp. 82

7
4. Connect 90° angle connector from coil cord to
handset.
5. Remove protective cover from connector at rear
of armrest.
6. Slide cord over spring, starting with the straight
connector. Clip last coil onto the front endof
the spring.
7. Connect straight connector to connector at rear
of armrest.
INSTALLING TRANSMITTER/RECEIVER (TR)
A. Model 129
B. Model 140
A. Model 129
1. Remove left trunk panel and taillamp assembly.
2. Assemble TRto mounting plate using brackets.
3. Attach pig-tail junction boxto plate, secure with cable tie.
4. Connect cable from junction boxtoTR.
5. Remove protective caps from studs in bottom of wheel well.
6. Partially remove carpeting from left trunk area.
7. Install clips to longitudinal rail over existing holes. Replace carpeting.
8. Position transmitter - receiver mounting plate over studs in wheel well. Insert sheet metal screws
through holes inTR plate into clips, donot tighten. Place nuts on studs and tighten. Tighten sheet
metal screws.
9. Connect white 4-pole connector (power supply) toTR.
10. Connect male speaker connector from vehicle harness to female speaker connector in junction box.
11. Disconnect 4-pole connector from antenna. Open connector locking strap. Insert bare connector
from antenna adapter harness into location "2"ofthe 4-pole connector. Insert from rear of
connector. Observe proper pin orientation. Close locking strap. Reconnect 4-pole connector to
antenna.
12. Connect 1-pole female junction box connector to round connector on antenna adapter harness.

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13. Connect telephone harness data cable to junction boxonTR plate.
14. Connect oneendofthe antenna lead cable totheTR,the other endtothe "Telefon" connection on
the splitter box.
15. Secure loose wires/cables with cable tie.
16. Reinstall left wheel well liner and taillamp
assembly.
17. Install 8 A fuse in auxiliary fuse box (located in
trunk, above battery, Figure 15).
18. Reconnect negative battery terminal.
19. Program telephone.
20. Recede radio.
21. Test function.
Figure 15
B. Model 140
1. Remove trunk mat, left trunk panel and taillamp
assembly.
2. Install TR onto metal plate (left of sound system
amplifier) using two clips (one at each end), and
#8x5/8" sheet metal screws. Make certain that
the antenna connector faces downward.
3. Connect oneendofthe antenna lead cable to
theTR,the other endtothe "Telefon"
connection onthe splitter box.
Figure 16 Model 140 Sedan
Figure 17 Model 140 Coupe

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4. Disconnect 4-pole connector from antenna. Open connector locking strap. Insert bare connector
from antenna adapter harness into location "2"ofthe 4-pole connector. Insert from rear of
connector. Observe proper pin orientation. Close locking strap. Reconnect 4-pole connector to
antenna.
5. Connect junction boxas follows:
a female speaker connector to male speaker
connector near white 4-pole TR power
connector
b 1-pole male antenna control connector to1-
pole round connector on antenna adapter
harness
cTR data connector toTR
d junction box connector to vehicle TR data
harness
Figure 18
6. Connect white 4-pole connector (power supply) toTR.
7. Secure adapter harness toTR mounting plate using cable ties.
8. Reinstall left wheel well liner and taillamp assembly.
9. Install 7.5A fuse in auxiliary fuse box (located in trunk, behind panel in right trunk liner).
10. Reconnect negative battery terminal.
11. Program telephone.
12. Recode radio.
13. Resynchronize window settings.
14. Test function.
INSTALLING HANDSFREE MICROPHONE
A. Model 129
B. Model 140
A. Model 129
1. Place template on headliner panel, so that it touches the left edge ofthe dome lamp assembly. Mark
location of mounting hole.
2. Remove dome lamp assembly.
W.I. 302a, Grp. 82