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![INFINITI QX4 2001 Factory Service Manual System DescriptionNBEL0079Refer to Owners Manual for audio system operating instructions.
Power is supplied at all times
Ithrough 15A fuse [No. 4, located in the fuse block (J/B)]
Ito audio unit term INFINITI QX4 2001 Factory Service Manual System DescriptionNBEL0079Refer to Owners Manual for audio system operating instructions.
Power is supplied at all times
Ithrough 15A fuse [No. 4, located in the fuse block (J/B)]
Ito audio unit term](/manual-img/42/57027/w960_57027-1344.png)
System DescriptionNBEL0079Refer to Owner's Manual for audio system operating instructions.
Power is supplied at all times
Ithrough 15A fuse [No. 4, located in the fuse block (J/B)]
Ito audio unit terminal 6,
Ito audio amp. relay terminal 3 and
Ito rear speaker amp. terminal 11.
With the ignition switch in the ACC or ON position, power is supplied
Ithrough 10A fuse [No. 10, located in the fuse block (J/B)]
Ito audio unit terminal 10.
Ground is supplied through the case of the audio unit.
Ground is supplied
Ito audio amp. relay terminal 2
Ithrough body grounds M4, M66 and M147
Ito front door speaker LH terminal 5 and
Ito front door speaker RH terminal 5
Ithrough body grounds M77 and M111
Ito rear speaker amp. terminal 24
Ithrough body grounds B11, B22 and D210.
When the audio unit POWER button is pressed, power is supplied
Ito rear speaker amp. terminal 9 and
Ito audio amp. relay terminal 1
Ifrom audio unit terminal 12.
Then audio amp. relay is energized and power is supplied
Ito front door speaker LH terminal 4 and
Ito front door speaker RH terminal 4.
Audio signals are supplied
Ithrough audio unit terminals 1, 2, 3, 4, 13, 14, 15 and 16
Ito terminals 2 and 6 of the LH and RH front speakers and terminals 5, 7, 18 and 20 of the rear speaker
amp.
Ito LH and RH tweeters through terminals 1 and 3 of the front speakers
Ito rear LH and RH speakers through terminals 1, 2, 25 and 26 of the rear speaker amp.
AUDIO
System Description
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SchematicNBEL0080
MEL817L
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AUDIO
Schematic
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Wiring Diagram Ð AUDIO ÐNBEL0081
MEL818L
AUDIO
Wiring Diagram Ð AUDIO Ð
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MEL819L
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AUDIO
Wiring Diagram Ð AUDIO Ð (Cont'd)
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MEL820L
AUDIO
Wiring Diagram Ð AUDIO Ð (Cont'd)
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MEL821L
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AUDIO
Wiring Diagram Ð AUDIO Ð (Cont'd)
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Trouble DiagnosesNBEL0082AUDIO UNITNBEL0082S01
Symptom Possible causes Repair order
Audio unit inoperative (no
digital display and no
sound from speakers).1. 10A fuse
2. Poor audio unit case ground
3. Audio unit1. Check 10A fuse [No. 10, located in fuse block (J/B)].
Turn ignition switch ON and verify that battery posi-
tive voltage is present at terminal 10 of audio unit.
2. Check audio unit case ground.
3. Remove audio unit for repair.
Audio unit presets are lost
when ignition switch is
turned OFF.1. 15A fuse
2. Audio unit1. Check 15A fuse [No. 4, located in fuse block (J/B)]
and verify that battery positive voltage is present at
terminal 6 of audio unit.
2. Remove audio unit for repair.
AM stations are weak or
noisy (FM stations OK).1. Antenna
2. Poor audio unit ground
3. Audio unit1. Check antenna.
2. Check audio unit ground.
3. Remove audio unit for repair.
FM stations are weak or
noisy (AM stations OK).1. Window antenna
2. Audio unit1. Check window antenna.
2. Remove audio unit for repair.
Audio unit generates noise
in AM and FM modes with
engine running.1. Poor audio unit ground
2. Loose or missing ground bonding
straps
3. Ignition condenser or rear window
defogger noise suppressor condenser
4. Alternator
5. Ignition coil or secondary wiring
6. Audio unit1. Check audio unit ground.
2. Check ground bonding straps.
3. Replace ignition condenser or rear window defogger
noise suppressor condenser.
4. Check alternator.
5. Check ignition coil and secondary wiring.
6. Remove audio unit for repair.
Audio unit generates noise
in AM and FM modes with
accessories on (switch
pops and motor noise).1. Poor audio unit ground
2. Antenna
3. Accessory ground
4. Faulty accessory1. Check audio unit ground.
2. Check antenna.
3. Check accessory ground.
4. Replace accessory.
Audio unit controls are
operational, but no sound
is heard from any speaker.1. 15A fuse
2. Audio unit output
3. Audio unit1. Check 15A fuse [No. 4, located in fuse block (J/B)].
Verify battery positive voltage is present at terminal 3
of audio amp. relay.
2. Check audio unit output voltage (Terminal 12).
3. Remove audio unit for repair.
All front speakers are inop-
erative.1. Audio amp. relay
2. Audio amp. relay ground
3. Amp. ON signal1. Check audio amp. relay.
2. Check audio amp. relay ground (Terminal 2).
3. Turn ignition switch ACC and audio unit ON. Verify
battery positive voltage is present at terminal 1 of
audio amp. relay.
Individual front speaker is
noisy or inoperative.1. Speaker ground
2. Power supply
3. Audio unit output
4. Speaker1. Check speaker ground (Terminal 5).
2. Check power supply for speaker (Terminal 4).
3. Check audio unit output voltage for speaker.
4. Replace speaker.
Both rear speakers are
inoperative.1. Poor rear speaker amp. ground
2. Power supply
3. Amp. ON signal
4. Rear speaker amp.1. Check rear speaker amp. ground circuit.
2. Check power supply for rear speaker amp. (Terminal
11).
3. Turn ignition switch ACC and audio unit ON. Verify
battery positive voltage is present at terminal 9 of
rear speaker amp.
4. Remove rear speaker amp. for repair.
Individual rear speaker is
noisy or inoperative.1. Speaker
2. Audio unit/amp. output
3. Speaker circuit
4. Audio unit1. Check speaker.
2. Check audio unit/amp. output.
3. Check wires for open or short between audio unit/
amp. and speakers.
4. Remove audio unit for repair.
AUDIO
Trouble Diagnoses
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InspectionNBEL0083AUDIO UNIT AND AMP.NBEL0083S01All voltage inspections are made with:
IIgnition switch ON or ACC
IAudio unit ON
IAudio unit and amps. connected (If audio unit or amp. is removed for inspection, supply a ground to the
case using a jumper wire.)
ANTENNANBEL0083S021. Using a jumper wire, clip an auxiliary ground between antenna and body.
IIf reception improves, check antenna ground (at body surface).
IIf reception does not improve, check main feeder cable for short circuit or open circuit.
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Inspection
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