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:
Editing the contact data
For PBAP compatible Bluetooth® phones, this function is available when “Automatic
Contact/History Transfer” is set to off. 1 Select “Edit Contact”.
2 Select the desired contact.
3 Select corresponding to the desired name or number.
► For editing the name
Follow the steps in “R ...
Replacement
Hint: components:
1. Precaution
2. Disconnect battery negative terminal
3. Remove instrument panel sub–assy lower
Remove the screw from the glove compartment door
stopper sub–assy.
pull the instrument panel sub–assy lower to remove it.
4. Separate passenger airbag co ...
Inspection procedure
1 Check d squib circuit(airbag sensor assy center – horn button
assy)
Disconnect the negative (–) terminal cable from the battery,
and wait at least for 90 seconds.
disconnect the connectors between the horn button assy
and the airbag sensor assy center.
for the blac ...