GMC 1976 ZEO 6083 Maintenance Manual page 637

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RADIO CUTS
RADIO STATIONS
ON-OFF
MIX TOGETHER
TURN RADIO ON
CHECK ELECTRICAL
CONNECTOR, ANTENNA
LEAD-IN PLUG AND
RADIO MOUNTING FOR
LOOSE CONNECTIONS .
JAR RADIO TO CHECK
RADIO CUTS
ON-OFF AS
CONNECTIONS
ARE MOVED
FOR INTERMITTENT
OPERATION .
CONNECTRADIO
SYSTEMS TESTER
J-22194 TO RADIO
TO CHECK SPEAKER
CAREFULLY TRIM RADIOAREFER SERVICE
MANUAL .) IF TWO OR MORE SIGNALS ARE
PICKED UP BY THE ANTENNA AT THE SAME
TIME, THERE IS NO WAY TO SEPARATE
THEM .
FUSE BLOWN
REPLACE FUSE
IF FUSE BLOWS
AGAIN,REMOVE
RADIO FOR
REPAIR
CONNECTORS LOOSE
OR DEFECTIVE
CHECK FUSE
RADIO DOES NOT PLAY
EVEN WITH SUBSTITUTE
SPEAKER.
FUSE OK
RADIO TROUBLE DIAGNOSIS
TURN ON RADIO AND
LISTEN FOR NORMAL
"THUMP"
CHECK RECEIVER AND
SPEAKER CONNECTORS
CONNECTORS
0. K.
THUMP HEARD
CHECK SPEAKER WITH RADIO
SYSTEMS TESTER J-22194, OR
SUBSTITUTE A KNOWN GOOD
SPEAKER OR SWITCH TO REAR
SPEAKER IF VEHICLE IS SO
EQUIPPED.
RADIO PLAYS
TURN ON RADIO AND BUMP RADIO
WITH HEEL OF HAND :
1 .CHECK SPARK PLUG WIRE FOR
BREAKDOWN, LOOSE OR IMPROPERLY
SEATED WIRE . MAKE SURE ALL
WIRES ARE TVRS TYPE .
2 .V-8 ENGINE, CHECK SHIELD OVER
IGNITION POINTS, TIGHTEN IF
LOOSE, REPLACE IF MISSING.
3. CHECK GROUND STRAPS FOR CLEAN
AND TIGHT CONNECTIONS .
4. CHECK ANTENNA LEAD-IN
CONNECTOR AT RADIO.
5. HAVE HELPER SIT IN VEHICLE TO
EVALUATE NOISE. USE A LARGE RAT
TAIL FILE AND BRIDGE ACROSS
FROM FRAME TO VARIOUS SECTIONS
OF EXHAUST SYSTEM . DO THE SAME
WITH FUEL TANK, ENGINE, FRONT
FENDERS, EEC. WHEN HELPER
RADIO NOISY
(STATIC)
REPORTS NOISE IS REDUCED CONNECT
BRAIDED GROUND STRAP TO FRAME
AND TO UNIT FILE WAS TOUCHING .
RADIO PLAYS
RADIO DEAD
REMOVE RADI
OR .RE PAIRS
CHECK LEAD-IN FROM
ANTENNA TO RADIO FOR
SHORT OR OPEN CIRCUIT.
WEAK RADIO SIGNAL
I [_
DISTORTED TONE
ONLY PICKS UP STRONG (SCRATCHY OR RASPY SOUND(
LOCAL STATIONS .
REMOVE RADIO
FOR REPAIR IF
PROBLEM WAS NOT
IN ANTENNA OR
LEAD IN .
TURN ON RADIO-ADJUST FOR
HIGH VOLUME AND MAXIMUM
BASS . CHECK SPEAKER WITH
RADIO SYSTEMS TESTER J-22194,
SUBSTITUTE A KNOWN GOOD
SPEAKER OR SWITCH TO REAR
SPEAKER IF VEHICLE IS SO
EQUIPPED.
NO DISTORTION(
DISTORTION
REPLACE SPEAKER
DEFECTIVE RECEIVER
REMOVE FOR SERVICING.
*NOTE : ON AM-FM RADIOS, ANTENNA TRIMMING IS ALWAYS
PERFORMED ON AM AND NEVER ON FM STATIONS .
VOLUME MUST BE TURNED FULL UP, RADIO TUNED
TO A WEAK STATION . NEAR 14011400 KC) ON THE DIAL .
IMPORTANT: AMIFMISTEREOITAPE
COMBINATION RADIOS HAVE A CON-
VECTOR .
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