DIAGNOSTIC CONDITIONS
NOISE DISTORTION IN ALL SPEAKERS
Does the distortion occur through all operations:
• AM and FM stations
• Cassette tape
• Compact disc
If not, check for radio interference, damaged tape
or disc that may be causing the distortion. Refer to
Sound Systems Operating Instructions in the Owners
Manual for cleaning procedures of the cassette tape
player.
• Check battery voltage, for 11 Volts or more
• Check amplifier connectors, and wires for proper
connection
• If OK, check radio, refer to Radio Diagnosis
• If OK, replace amplifier
ELECTRICAL NOISE DISTORTION ONE SPEAKER
• Remove output signal connector from amplifier
and check for short to ground on the speaker with
the distortion. Refer to Group 8W, Wiring Diagrams
for the appropriate pin numbers.
• If shorted to ground, disconnect speaker connec-
tor and recheck from the amplifier for short to
ground.
• If still shorted to ground, repair wires. Not
shorted to ground, replace speaker.
• Not shorted to ground, check speaker resistance
at amplifier connector for2-16ohms.
• If resistance is OK, refer to Radio Diagnosis. If
radio checks OK, replace amplifier.
• If resistance is less than two ohms, replace
speaker. If resistance is OK, repair wires
MECHANICAL NOISE DISTORTION
• Check trim for loose parts, and speaker attach-
ments for buzzes
• Remove speaker that is still connected and lis-
ten for distortion. If distortion remains, replace
speaker.
ONE SPEAKER NON-OPERATIVE
• Remove output signal connector from amplifier
and check for2-16ohms resistance to the non-op-
erative speaker. Refer to Group 8W, Wiring Diagrams
for the appropriate pin numbers.
• If resistance is less than two ohms, test speaker
for resistance.
• If OK, repair wire. If not OK, replace speaker.
ALL SPEAKERS NON-OPERATIVE
• Check radio for being ON, are the display lights
on
• Radio not ON, refer to Radio Diagnosis
• Check fuses, amplifier connectors and wires for
proper connection
• Check for good ground
• Check amplifier, for battery voltage and
ON/OFF voltage
(1) Battery voltage OK and NO voltage at the
ON/OFF terminal, check for short or open in the
ON/OFF circuit.
(2) ON/OFF voltage OK, and NO battery voltage,
check for short or open in battery circuit.
(3) Prior to replacing amplifier check fuse to the
cigar lighter and horn. If not OK, replace fuse. If fuse
blows again disconnect amplifier B+ wire connector.
Refer to Group 8W, Wiring Diagrams for the proper
connector.
(4) If fuse still blows the problem is not the ampli-
fier. If fuse does not blow replace the amplifier.
(5) If shorted or open circuit repair as necessary.
SPEAKER RESISTANCE
SPEAKER RESISTANCE VALUE
MIDLINE 2.5” FRONT OR WINDOW SPEAKER 13 - 16 OHMS
INFINITY 2.5” FRONT OR WINDOW SPEAKER 3 - 5 OHMS
MIDLINE - ALL OTHER SPEAKERS 6.5 - 8.5OHMS
INFINITY - ALL OTHER SPEAKERS 2 - 3 OHMS
REAR WINDOW ANTENNA
NOTE: Due to a capacitor integral with the coaxial
cable, the coax cable can not be tested. The conti-
nuity test between the center pin of the coax to the
antenna does not apply. An ohm meter check to the
center pin of the coaxial cable will falsely indicate
an open circuit. The coaxial shield to ground test
can be performed. Verify coaxial cable performance
by using a known good cable.
Before performing any antenna service procedures,
verify that Rear Window Defogger is operating prop-
erly (Fig. 4) and (Fig. 5). If no, repair as necessary.
LH AUDIO SYSTEMS 8F - 15
DIAGNOSIS AND TESTING (Continued)
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