1995 JEEP YJ radio

ANTENNA
All models use a fixed-length stainless steel rod-
type antenna mast, installed at the right front (fend-
er on XJ, cowl side on YJ) of the vehicle. The
antenna mast is connected to the center wire of the
coaxial antenna cable and is not grounded to any
part of the vehicle.
To eliminate static, the antenna base must have a
good ground. The coaxial antenna cable shield (the
outer wire mesh of the cable) is grounded to the an-
tenna base and the radio chassis.
The factory installed ETRs automatically compen-
sate for radio antenna trim. Therefore, no antenna
trimmer adjustment is required or possible when re-
placing the receiver or the antenna.
RADIO NOISE SUPPRESSION
Radio Frequency Interference (RFI) and Electro-
Magnetic Interference (EMI) noise suppression is ac-
complished primarily through circuitry internal to
the radio receivers. These internal suppression de-
vices are only serviced as a part of the radio receiver.External suppression devices that are serviceable
and should be checked in the case of RFI or EMI
noise complaints include the following:
²radio antenna base ground
²engine-to-body ground strap
²resistor-type spark plugs
²radio suppression-type secondary ignition wiring.
In addition, if the source of RFI or EMI noise is
identified as a component on the vehicle (i.e.:genera-
tor, blower motor, etc.), the ground path for that com-
ponent should be checked. If excessive resistance is
found in that circuit, repair as required before con-
sidering any component replacement.
Fleet vehicles are available with an extra-cost RFI-
suppressed Powertrain Control Module (PCM). This
unit reduces interference generated by the PCM on
some radio frequencies used in two-way radio com-
munications. However, this unit will not resolve com-
plaints of RFI in the commercial AM or FM radio
frequency ranges.
DIAGNOSIS
RADIO
CAUTION: Do not operate the radio with speaker
leads detached since damage to the transistors
may result.
(1) Check fuse 2 in fuseblock module and fuse in
back of radio chassis. If OK, go to next step. If not
OK, replace fuse.
(2) Turn ignition switch to ON position. Check for
battery voltage at fuse 2. If OK, go to next step. If
not OK, repair circuit to ignition switch as required.
(3) Turn ignition switch to OFF position. Discon-
nect battery negative cable. Remove instrument clus-
ter bezel. Remove radio, but do not unplug any
connections. Check for continuity between the radio
chassis and a good ground. There should be continu-
ity. If OK, go to next step. If not OK, repair radio
ground circuit as required.
(4) Connect battery negative cable. Turn ignition
switch to ON position. See Radio Connections chart.
Check for battery voltage at cavity 3 of radio connec-
tor. If OK, go to next step. If not OK, repair circuit to
fuse 2 as required.
(5) Turn ignition switch to OFF position. Check for
battery voltage at cavity 4 of radio connector. If OK,
replace radio. If not OK, repair circuit to IOD fuse in
PDC as required.
SPEAKERS
CAUTION: Do not operate the radio with speaker
leads detached since damage to the transistors
may result.
(1) Turn radio on and adjust balance and fader
controls to check performance of each individual
speaker. Note the speaker locations that are not per-
forming correctly. Go to next step.
(2) Turn radio off. Disconnect battery negative ca-
ble. Remove instrument cluster bezel and remove ra-
dio. See Radio Connections chart. Check both the
speaker feed and return cavities at radio for continu-
ity to a good ground. There should be no continuity.
If OK, go to next step. If not OK, repair wiring cir-
cuit as required.
(3) Check resistance between speaker feed and re-
turn cavities. Meter should read between 3 and 8
ohms (speaker impedance). If OK, see diagnosis for
Radio. If not OK, go to next step.
(4) Unplug speaker wiring connector. Check for
continuity between speaker feed cavity at radio and
at speaker. Repeat check between speaker return
cavity at radio and at speaker. If OK, replace
speaker. If not OK, repair wiring circuit as required.
8F - 2 AUDIO SYSTEMSJ

RADIO DIAGNOSIS
JAUDIO SYSTEMS 8F - 3

RADIO ILLUMINATION RELAY
If the relay fails any one of Relay Tests, it is faulty
and should be replaced. If the relay passes the Relay
Tests, proceed to the Relay Circuit Tests.
On XJ models, the radio illumination relay is lo-
cated in the relay center (Fig. 2), which is fastened to
the lower instrument panel reinforcement behind the
lower instrument panel near the steering column. On
YJ models, the relay is taped to the instrument panel
wiring harness above and to the right of the radio,
near the glove box.
RELAY TESTS
Remove relay to perform the following tests:
(1) A relay in the de-energized position should
have continuity between terminals 87A and 30, and
no continuity between terminals 87 and 30.(2) Resistance value between terminals 85 and 86
(electromagnet) is 7565 ohms.
(3) Connect a battery to terminals 85 and 86. There
should now be continuity between terminals 30 and 87,
and no continuity between terminals 87A and 30.
RELAY CIRCUIT TESTS
With relay still removed, perform the following
tests:
(1) The common feed terminal (30) is connected to
the radio display feed circuit. There should be conti-
nuity between cavity for relay terminal 30 and clock/
radio display feed cavity of radio connector at all
times. If not, repair circuit as required.
(2) The normally closed terminal (87A) is connected
to terminal 30 in the de-energized position. This circuit
provides ignition-switched battery voltage to the radio
display when the headlamp switch is off. There should
be battery voltage present at cavity for relay terminal
87A with the ignition switch in the ON position. If not,
repair circuit to ignition switch as required.
(3) The normally open terminal (87) is connected to
terminal 30 in the energized position. This circuit
provides instrument panel dimmer controlled feed to
the radio display when the headlamp switch is on.
There should be voltage present at cavity for relay
terminal 87 when the headlamp switch is on. Also,
the voltage reading should vary as the panel dimmer
switch is rotated. If not, repair circuit or panel dim-
mer switch as required.
(4) The coil battery terminal (86) connected to the
electromagnet in the relay. Check as follows:
(a) On YJ models, it is energized when the head-
lamp switch is on. There should be battery voltage at
cavity for relay terminal 86 with the headlamp switch
on. If not, repair circuit to headlamp switch as re-
quired.
(b) On XJ models, it is grounded at all times.
There should be continuity to ground at cavity for
relay terminal 86 at all times. If not, repair circuit
to ground as required.
RADIO CONNECTIONS
Fig. 2 Radio Illumination Relay - XJ
RADIO ILLUMINATION RELAY CONNECTIONS
8F - 4 AUDIO SYSTEMSJ

(5) The coil ground terminal (85) is connected to
the electromagnet in the relay. Check as follows:
(a) On YJ models, it is grounded at all times.
There should be continuity to ground at cavity for
relay terminal 85 at all times. If not, repair circuit
to ground as required.
(b) On XJ models, it is energized when the head-
lamp switch is on. There should be battery voltage
at cavity for relay terminal 85 with the headlamp
switch on. If not, repair circuit to headlamp switch
as required.
ANTENNA
The following four tests are used to diagnose the
antenna with an ohmmeter:
²mast to ground test (Test 1)
²tip-of-mast to tip-of-conductor test (Test 2)
²body ground to battery ground test (Test 3)
²body ground to coaxial shield test (Test 4).
Ohmmeter test lead connections for each test are
shown in Figure 3.
TEST 1
Test 1 determines if the antenna mast is insulated
from the base. Proceed as follows:
(1) Disconnect antenna cable lead from radio chas-
sis and isolate.
(2) Connect one ohmmeter lead to tip of antenna
mast and the other lead to the antenna base. Check
for continuity.
(3) There should be no continuity. If continuity is
found, replace defective or damaged antenna base
and cable assembly.
TEST 2
Test 2 checks the antenna for an open circuit as fol-
lows:
(1) Disconnect the antenna cable lead from the ra-
dio chassis.
(2) Connect one ohmmeter test lead to tip of an-
tenna mast. Connect remaining lead to tip of an-
tenna cable lead (the part inserted into the radio).
(3) Continuity should exist (ohmmeter should only
register a fraction of an ohm). High or infinite resis-
tance indicates damage to the base and cable assem-
bly. Replace if required.
TEST 3
Test 3 checks condition of the vehicle body ground
connection as follows:
(1) Connect one ohmmeter test lead to the vehicle
fender and the other lead to the battery negative
post.
(2) Resistance should be less than one ohm.
(3) If resistance is more than one ohm, check the
braided ground strap connected to the engine and ve-
hicle body for being loose, corroded, or damaged. Re-
pair as necessary.
TEST 4
Test 4 checks condition of the ground between the
antenna base and vehicle body as follows:
(1) Connect one ohmmeter test lead to the fender
and the other lead to the crimp on the coaxial an-
tenna cable shield.
(2) Resistance should be less then one ohm.
(3) If resistance is more then one ohm:
(a) On YJ models, replace the antenna base at-
taching screws with new cadmium plated screws.
(b) On XJ models, clean and/or tighten antenna
base to fender mounting hardware.
RADIO FREQUENCY INTERFERENCE
Inspect ground connections at:
²blower motor
²electric fuel pump
²generator
²ignition module
²wiper motor
²antenna coaxial ground
²radio ground
²body-to-engine ground strap (braided).
Clean, tighten or repair as required.
Also inspect the following secondary ignition sys-
tem components:
²spark plug wire routing and condition
²distributor cap and rotor
²ignition coil
²spark plugs.
Reroute spark plug wires or replace components as
required.
Fig. 3 Antenna Tests
JAUDIO SYSTEMS 8F - 5

SERVICE PROCEDURES
RADIO REMOVE/INSTALL - XJ
(1) Disconnect battery negative cable.
(2) Remove upper and lower steering column
shrouds and steering column to instrument panel be-
zel gap hider. If equipped with tilt steering, apply
tape to tilt mechanism on top of steering column to
protect instrument panel bezel from damage during
removal.
(3) Remove 4 instrument panel bezel attaching
screws (Fig. 4) and remove the bezel.
(4) Remove 2 radio attaching screws (Fig. 5).(5) Slide radio chassis out of instrument panel far
enough to disconnect radio electrical connector,
ground lead and antenna lead (Fig. 6). Remove radio
from instrument panel.
(6) To install radio, route harness above and to the
right of the radio cavity. Make radio harness, ground
and antenna connections.
(7) While installing the radio, make sure that clip
on top of radio (Fig. 7) is installed in mating slot of
instrument panel.
(8) Reverse removal procedures to complete instal-
lation.
SPEAKERS REMOVE/INSTALL - XJ
INSTRUMENT PANEL
(1) Remove parking brake retaining screw from
lower instrument panel (Fig. 8).
(2) Remove retaining screws and the lower instru-
ment panel (Fig. 9).
(3) Unplug wire harness connector.
(4) Remove speaker screws and speaker from lower
instrument panel (Fig. 10).
(5) Reverse removal procedures to install.
Fig. 4 Instrument Bezel Remove/Install - XJ
Fig. 5 Radio Mounting Screws Remove/Install - XJ
Fig. 6 Radio Wiring Remove/Install - XJ
Fig. 7 Radio Clip Install - XJ
8F - 6 AUDIO SYSTEMSJ

(2) Carefully remove grille from speaker by placing
fingertips on outer circumference of grille and gently
prying straight down to disengage 4 mounting tabs.
(3) Drill out rivets securing speaker to sound bar.
(4) Lower speaker far enough to unplug wiring
from connector.
(5) Reverse removal procedures to install. Use new
rivets to secure speaker. Be certain that tabs on
speaker grille are inserted through slots in sound
bar.
SOUND BAR REMOVE/INSTALL - XJ
(1) Disconnect battery negative cable.
(2) Remove lens from cargo lamp housing.
(3) Remove screws securing left and right rear side
roof rail garnish moldings.
(4) Remove left and right rear side roof rail gar-
nish moldings.
(5) Remove 2 push-on retainers from pins inside
cargo lamp housing securing sound bar to rear roof
bow.
(6) Lower sound bar from roof area and remove
from vehicle.
(7) Reverse removal procedures to install. Use 2
new push-on retainers.
ANTENNA REMOVE/INSTALL - XJ
(1) Remove the fender inner splash panel mount-
ing nuts (Fig. 14) and move the panel aside to gain
access to the antenna base and cable.
The splash panel screws may be covered with
undercoating.
(2) Remove the antenna mast, nut and antenna
pad from the top of the fender (Fig. 15).
(3) Remove the passenger side kick panel.
(4) Disconnect the antenna lead (Fig. 16) by pull-
ing apart while twisting the metal connectors. DO
NOT PULL ON THE COAXIAL CABLE.
(5) Pull the rubber grommet out of the kick panel.(6) Remove the antenna assembly from inside the
wheel well.
(7) Reverse removal procedures to install.
(8) Verify antenna and radio operation.
Fig. 13 Trim Panel Remove - XJ
Fig. 14 Fender Inner Splash Panel Remove/Install -
XJ
Fig. 15 Nut and Antenna Pad Remove/Install - XJ
8F - 8 AUDIO SYSTEMSJ

(9) Apply a rubberized undercoating material to
the splash panel screws.
RADIO REMOVE/INSTALL - YJ
(1) Disconnect battery negative cable.
(2) Remove center cluster bezel attaching screws
(Fig. 17).
(3) Remove radio bezel.
(4) Remove radio attaching screws.
(5) Disconnect radio antenna cable.
(6) Disconnect radio wire harness.
(7) Remove radio.
(8) Reverse removal procedures to install.
SPEAKERS REMOVE/INSTALL - YJ
INSTRUMENT PANEL - YJ
RIGHT SIDE
The speaker is located behind grille panel at right
end of the instrument panel.
(1) Reach up behind instrument panel and remove
4 stamped nuts holding the speaker in place.
(2) Disconnect speaker electrical connector and re-
move speaker.
LEFT SIDE
The speaker is located behind grille panel at left
end of the dash panel.
(1) Remove nuts that attach the park brake assem-
bly mounting studs to the dash panel. The nuts are
accessible from the engine compartment (Fig. 18).
CAUTION: If vehicle is equipped with a rear window
wiper, there is a ground wire attached to top of bolt
that attaches the park brake assembly to the instru-
ment panel.
(2) Remove bolt that attaches the park brake as-
sembly to the instrument panel and allow assembly
to fall out of the way.
(3) Reach up behind instrument panel and remove
4 stamped nuts holding speaker in place.
(4) Disconnect speaker electrical connector and re-
move speaker.
(5) Reverse removal procedures to install.
SOUND BAR - YJ
(1) Pull sound bar padding away from bar on the
passenger side (Fig. 19).
(2) Disconnect speaker harness connector located
on the passenger side at the sound bar.
Fig. 16 Disconnect Antenna Lead - XJ
Fig. 17 Center Cluster Bezel Remove/Install - YJ
Fig. 18 Park Brake Assembly - YJ
JAUDIO SYSTEMS 8F - 9

(3) Remove screws holding speaker grille and
speaker to bar.
(4) Disconnect wires from speaker and remove
speaker.
(5) Reverse removal procedures to install.
SOUND BAR REMOVE/INSTALL - YJ
(1) Disconnect speaker harness connector located
on the passenger side at the sound bar (Fig. 19)
(2) Remove bolts attaching the sound bar side
flanges to the right and left side bars.
(3) Open zipper on sport bar cover.
(4) Remove bolts attaching the sound bar brackets
to the sport bar (located on the rear of the sport bar)
(Fig. 20). Slip brackets through the sport bar cover.
(5) Reverse removal procedures to install.
ANTENNA REMOVE/INSTALL - YJ
(1) Remove the radio. See Radio Remove/Install, in
this group for procedures.
(2) Remove three screws holding the antenna base
and pad to the body (Fig. 21).
(3) Pull the antenna and cable out of the vehicle.(4) To install the antenna, make sure the antenna
pad is placed over the cable and guide the cable un-
der the instrument panel.
(5) Secure the antenna base and pad with three
screws.
(6) Install the antenna lead into the radio and in-
stall the radio.
Fig. 19 Sound Bar Speaker Connector - YJ
Fig. 20 Sound Bar Attaching Bolt - YJ
Fig. 21 Antenna Remove/Install - YJ
8F - 10 AUDIO SYSTEMSJ