Toyota Corolla (E120) 2002–2008 Repair Manual / Diagnostics / Audio system / Sound quality is bad in all modes (volume is too low)
Toyota Corolla (E120): Sound quality is bad in all modes (volume is too low)
Wiring diagram
Inspection procedure
1 Adjust sound quality
- Adjust the sound quality.
- Operate the radio receiver assy to adjust the sound quality.
Standard: malfunction disappear.


2 Compare it with another car of same model
- Compare it with another vehicle of the same model.
- Compare with the vehicle of the same type which does not have a
trouble to see if there is any
difference in the condition of trouble occurrence.
Standard: no difference found.


3 Check harness and connector(between radio receiver assy and speaker)


4 Inspect front no.1 Speaker assy
- Preparation for check
- disconnect the connector of the speaker.
- resistance check
- check the resistance between the terminals of the speaker.
Notice
: the speaker should not be removed for checking.
Standard value: 4 Ω


5 Inspect front no.2 Speaker assy
- Check that malfunction disappear when a known good speaker is installed.
Standard: malfunction disappear.
Hint
: connect the all connectors of speakers.


6 Inspect rear speaker assy
- Preparation for check
- disconnect the connector of the speaker.
- resistance check
- check the resistance between the terminals of the speaker.
Notice
: the speaker should not be removed for checking.
Standard value: 6 Ω


7 Inspect radio receiver assy(+b, acc, gnd)

- Check that the continuity between terminals at each condition, as shown in the chart.
Standard:

- Check that the voltage between terminals at each condition, as shown in the chart.
Standard:



Repair or replace harness or connector
Other materials:
Antenna cord sub–assy
Replacement
Hint: components:
1. Remove instrument panel sub–assy upper
Hint:
refer to the procedure until the step, ”remove instrument panel sub–assy
upper” of
instrument panel sub–assy lower.
Remove the related parts as long as the antenna cord sub–assy can be
removed ...
Indicators
The indicators inform the driver of the operating state of the vehicle’s various
systems.
*1: Vehicles without a smart key system:
These lights turn on when the engine switch is turned to the “ON” position to indicate
that a system check is being performed. They will turn off after the ...
Receiving a phone call
Answering the phone
Press the off-hook switch.
Refusing a call
Press the on-hook switch.
Receiving a call when on another call
Press the off-hook switch.
Pressing the off-hook switch again returns you to the previous call.
Adjusting the ringtone volume when receiving a call
Change the ringto ...


