Audio System: Diagnosis — Audio System — Entertainment Systems

PROBLEM SYMPTOMS TABLE

Note. When replacing the internal mechanism (computer part) of the audio system, be careful that no part of your body or clothing comes in contact with the terminals of the leads from the IC, etc. of the replacement part (spare part).

HINT

This inspection procedure is a simple troubleshooting which should be carried out on the vehicle during system operation and was prepared on the assumption of system component troubles (except for the wires and connectors, etc.).

Always inspect the trouble taking the following items into consideration.

Open or short circuit of the wire harness
Connector or terminal connection fault

	Problem	Refer to
Radio	Radio not operating when power switch turned to 'ON'.	1
	Display indicates when power switch turned to 'ON', but no sound (including 'noise') is produced.	2
	Noise present, but AM - FM not operating.	3
	Any speaker does not work.	4
	Any AM or FM does not work.	5
	Few preset turning bands.	5
	Reception poor.	6
	Sound quality poor.	7
	Preset memory disappears.	8
Tape Player	Cassette tape cannot be inserted.	9
	Cassette tape inserted, but no power.	10
	Power coming in, but tape player not operating.	11
	Any speaker does not work.	12
	Sound quality poor.	13
	Tape jammed, malfunction with tape speed or auto-reverse.	14
	Cassette tape will not eject.	15
CD Player	CD cannot be inserted.	16
	CD inserted, but no power.	17
	Power coming in, but CD player not operating.	18
	Sound jumps.	19
	Sound quality poor (Volume faint).	20
	Any speaker does not work.	21
	CD will not be ejected.	22
Stereo Component Amplifier	No power coming in.	23
	Power coming in, but Stereo component amplifier not operating.	24
	Any speaker does not work.	25
Noise	Noise occurs	26
	Noise produced by vibration or shock while driving.	27
	Noise produced when engine starts.	28

PROBLEM SYMPTOM

The term "AM" includes LW, MW and SW, and the term "FW" includes UKW.

DIAGNOSTIC PROCEDURES

RADIO

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Scheme 7: DIAGNOSTIC PROCEDURES

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RADIO NOT OPERATING WHEN POWER SWITCH TURNED TO "ON"
DISPLAY INDICATES WHEN POWER SWITCH TURNED TO "ON", BUT NO SOUND (INCLUDING "NOISE") IS PRODUCED
NOISE PRESENT, BUT AM-FM NOT OPERATING
ANY SPEAKER DOES NOT WORK
ANY AM OR FM DOES NOR WORK FEW PRESET TUNING BANDS
POOR RECEPTION
SOUND QUALITY POOR
PRESET MEMORY DISAPPEARS
CASSETTE TAPE CANNOT BE INSERTED
CASSETTE TAPE INSERTED, BUT NO POWER
POWER COMING IN, BUT TAPE PLAYER NOT OPERATING
ANY SPEAKER DOES NOT WORK
SOUND QUALITY POOR (VOLUME FAINT)
TAPE JAMMED MALFUNCTION WITH TAPE SPEED OR AUTO-REVERSE
CASSETTE TAPE WILL NOT BE EJECTED
CD CANNOT BE INSERTED
CD INSERTED, BUT NO POWER
POWER COMING IN, BUT CD PLAYER NOT OPERATING
SOUND JUMPS
SOUND QUALITY POOR (VOLUME FAINT)
ANY SPEAKER DOES NOT WORK
CD WILL NOT BE EJECTED
NO POWER COMING IN
POWER COMING IN, BUT WOOFER (POWER) AMPLIFIER NOT OPERATING
ANY SPEAKER DOES NOT WORK
NOISE OCCURS
NOISE PRODUCED BY VIBRATION OR SHOCK WHILE DRIVING
NOISE PRODUCED WHEN ENGINE STARTS

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Scheme 35: LOCATION

The vehicle (Scheme 36)is "GS430.
All components of "GS300" other than the ones used for engine are same as "GS430".

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Scheme 36: INSPECTION

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INSPECT CD AUTO CHANGER CIRCUIT Disconnect connectors from CD auto changer and inspect the connector on the wire harness side. TESTER CONNECTION SPECIFIED CONDITION Tester connection Condition Specified condition 1 - Ground Constant Battery positive voltage 6 - Ground Ignition switch LOCK No voltage 6 - Ground Ignition switch ACC or ON Battery positive voltage 8 - Ground Constant Continuity If the circuit is not as specified, inspect the circuits connected to other parts. HINT: Check the wire harness between the radio receiver assembly and the CD auto changer. Since the signals to and from the MUTE(3), CDL+(2), CDL-(7), CDR+(1), CDR-(6), TXM- (9) and TX+(4) terminals are serial signals, they cannot ordinarily be measured with a tester.
INSPECT POWER AMPLIFIER CIRCUIT (PIONEER made) Disconnect the connector from power amplifier and inspect the connector on the wire harness side. TESTER CONNECTION SPECIFIED CONDITION Tester connection Condition Specified condition B4 - Ground Constant Battery positive voltage B7 - Ground Constant Continuity C12 - Ground Ignition switch LOCK and radio switch ON No voltage C12 - Ground Ignition switch ACC or ON and radio switch ON Battery positive voltage If the circuit is not as specified, inspect the circuits connected to other parts.
INSPECT POWER AMPLIFIER CIRCUIT (MARK LEVINSON made) Disconnect the connector from power amplifier and inspect the connector on the wire harness side. TESTER CONNECTION SPECIFIED CONDITION Tester connection Condition Specified condition A7 - Ground Constant Battery positive voltage A12 - Ground Constant Continuity A13 - Ground Constant Continuity A16 - Ground Constant Battery positive voltage B20 - Ground Ignition switch ACC Battery positive voltage If the circuit is not as specified, inspect the circuits connected to other parts.
INSPECT RADIO RECEIVER ASSEMBLY CIRCUIT (USA and CANADA models) Disconnect the connectors from the radio receiver assembly, and inspect the connector on the wire harness side. TESTER CONNECTION SPECIFIED CONDITION Tester connection Condition Specified condition A1 - Ground Ignition switch LOCK No voltage A1 - Ground Ignition switch ACC or ON Battery positive voltage A2 - Ground Constant Continuity A4 - Ground Constant Battery positive voltage If the circuit is not as specified, inspect the circuits connected to other parts. HINT: Check the wire harness between radio receiver assembly and the CD auto changer, between radio receiver assembly and power amplifier.
INSPECT RADIO RECEIVER ASSEMBLY CIRCUIT (TAIWAN models) Disconnect the connectors from the radio receiver assembly, and inspect the connector on the wire harness side. TESTER CONNECTION SPECIFIED CONDITION Tester connection Condition Specified condition A1 - Ground Ignition switch LOCK No voltage A1 - Ground Ignition switch ACC or ON Battery positive voltage A2 - Ground Constant Continuity A4 - Ground Constant Battery positive voltage If the circuit is not as specified, inspect the circuits connected to other parts. HINT: Check the wire harness between radio receiver assembly and the CD auto changer, between radio receiver assembly and power amplifier.
INSPECT GATEWAY ECU CIRCUIT Disconnect the connectors from the gateway ECU, and inspect the connector on the wire harness side. TESTER CONNECTION SPECIFIED CONDITION Tester connection Condition Specified condition 2 - Ground Ignition switch ON Battery positive voltage 7 - Ground Constant Continuity 8 - Ground Constant Battery positive voltage 9 - Ground Ignition switch ACC Battery positive voltage 14 - Ground Constant Continuity If the circuit is not as specified, inspect the circuits connected to other parts. HINT: Check the wire harness between radio receiver assembly and the gateway ECU.

Audio System: Diagnosis Lexus GS III