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

  1. Adjust the sound quality.
  1.  Operate the radio receiver assy to adjust the sound quality.

    Standard: malfunction disappear.

2 Compare it with another car of same model

2 Compare it with another car of same model

  1. Compare it with another vehicle of the same model.
  1.  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

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

4 Inspect front no.1 Speaker assy

4 Inspect front no.1 Speaker assy

  1. Preparation for check
  1.  disconnect the connector of the speaker.
  1.  resistance check
  1.  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

5 Inspect front no.2 Speaker assy

  1. 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

6 Inspect rear speaker assy

  1. Preparation for check
  1.  disconnect the connector of the speaker.
  1.  resistance check
  1.  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)

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

  1. Check that the continuity between terminals at each condition, as shown in the chart.

Standard:

  1. Check that the voltage between terminals at each condition, as shown in the chart.

Standard:

Repair or replace harness or connector

Repair or replace harness or connector

    Share this page:

    Other materials:

    Inspection procedure
    Hint: read freeze frame data using the hand-held tester or the obd ii scan tool. Freeze frame data records the engine conditions when a malfunction is detected. When troubleshooting, it is useful for determining whether the vehicle was running or stopped, the engine was warmed up or not, the ...

    Driving assist systems
    To keep driving safety and performance, the following systems operate automatically in response to various driving situations. Be aware, however, that these systems are supplementary and should not be relied upon too heavily when operating the vehicle. Summary of the driving assist systems ■ ABS ( ...

    Foreword
    This repair manual has been prepared to provide essential information on body panel repair methods (including cutting and welding operations, but excluding painting) for the toyota corolla Applicable models: aze141 series zre142 series This manual consists of body repair methods, exploded diag ...