NO.1 AF NOISE OR POP NOISE AT ALL SOURCES (RADIO, CD) [AUDIO]

id0903e1817600

1

AF noise or POP noise at all sources (Radio, CD)/Possible DTC: 09:Er20, 09:Er21 / Device code 09/error code 20, 21
Troubleshooting hints
•  Low vehicle battery voltage.
•  Jammed radio signals from after market equipment.
•  Speaker malfunction (e.g., any foreign material, broken)
•  Improper speaker installation
•  Poor connection of audio unit/car-navigation unit connector, terminal damage
•  Poor connection of audio amplifier connector, terminal damage
•  Antenna malfunction (e.g., poor ground)
•  audio unit/car-navigation unit malfunction
•  Audio amplifier malfunction (with Bose ®)
Note
•  AF noise is “Petit petit” noise that generally occurs with switch ON/OFF operations of electrical equipment other than the audio unit/car-navigation unit, or “Gee” continual noise that occurs when electrical equipment is operated. This is caused by noise entrance to the power supply wiring, signal wiring, speaker cable or head of cassette deck. etc. Therefore noise can be heard regardless of radio wave condition of audio volume position. The noise will start after one click from the minimum position of volume switch but normally does not change even when volume is turned to higher position.
•  POP noise is “Putsun”, “Poco” or “Putsun” noise that occurs with switch ON/OFF operation of the audio unit/car-navigation unit, or with switching Radio to CD. Even normal audio unit/car-navigation unit sometimes emits small noise depending on conditions.

Diagnostic procedure

STEP

INSPECTION

ACTION
1
•  Inspect the vehicle battery voltage.
•  Is the vehicle battery voltage normal?
Specification:
Ignition switch ON: 11.5 V or more
Idle: 12.5 V or more
Yes
Go to the next step.
No
Charge the battery, then go to the next step.
2
•  Turn the audio unit/car-navigation unit power to ON.
•  Is there any noise?
Yes
Go to the next step.
No
The system is normal. Explain to the customer that the vehicle battery voltage was low.
3
•  Is any of the following after-market equipment installed? (Inspect especially near the antenna.)
―  Radar
―  Remote engine starter
―  Anti-theft device
―  Other
Yes
Go to the next step.
No
Go to Step 5.
4
•  Remove the after-market equipment.
•  Turn the audio unit/car-navigation unit power to ON.
•  Is there any noise?
Yes
Go to the next step.
No
The system is normal. The after-market electrical devices might make a noise.
5
•  Is there the noise from all the speakers?
Yes
Go to Step 7.
No
Go to the next step.
6
•  Inspect the suspect speaker.
•  Is the speaker normal?
Yes
Go to the next step.
No
If there is any foreign material to the speaker:
•  Remove the foreign material from the speaker.
If the speaker is malfunctioning:
•  Replace the speaker.
If the speaker is not installed properly:
•  Install the speaker properly.
7
•  Attempt to duplicate the symptom on the other vehicle.
•  Is the noise better than the customers vehicle?
Yes
Go to the next step.
No
The system is normal. Explain the noise generation mechanism to the customer.
Note
•  The noise may be heard depends on the operating speed of the audio power and/or mode switch.
8
•  Turn the ignition switch to the LOCK position.
•  Remove the audio unit/car-navigation unit.
•  Inspect the connection of the audio unit/car-navigation unit connector (24-pin) (for sound signal line).
•  Is the connector connected securely?
Yes
Go to the next step.
No
If poor connection of audio unit/car-navigation unit connector:
•  Security connect the audio connector.
If the audio unit/car-navigation unit side connector is wrong:
•  Replace the audio unit/car-navigation unit.
If the wiling harness-side connector is wrong:
•  Repair or replace the pins and/or the connector.
After treating either the above-mentioned, then go to the next step.
9
•  Is there any noise?
Yes
Go to the next step.
No
The system is normal.
10
•  Inspect the ground condition of the antenna.
•  Is the ground condition normal?
Yes
Replace the audio unit/car-navigation unit. Go to the next step.
(See CENTER PANEL UNIT REMOVAL/INSTALLATION.)
(See CENTER PANEL UNIT DISASSEMBLY/ASSEMBLY.)
No
Repair or replace the ground. Go to the next step.
11
•  Is there any noise?
Yes
Without BOSE®:
•  Replace the audio unit/car-navigation unit.
With BOSE®::
•  If noise occurs from the speaker of a specific channel, or the volume is minimized and the noise occurs:
―  Replace the audio amplifier.
•  If the noise occurs from the speaker of two or more channels or the volume is minimized and the noise does not occurs:
―  Replace the audio unit/car-navigation unit.
No
The system is normal.