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:

    Side mudguard sub–assy lh
    Replacement Hint: use the same procedures for the rh side and lh side. 1. Remove side mudguard sub–assy lh Using a clip remover, remove the 8 retainers and 9 clips.  using a moulding remover, remove the mudguard. 2. Install side mudguard sub–assy lh Install the mudgu ...

    Battery
    Check the battery as follows. ■ Battery exterior Make sure that the battery terminals are not corroded and that there are no loose connections, cracks, or loose clamps. 1 Terminals 2 Hold-down clamp ■Before recharging When recharging, the battery produces hydrogen gas which is ...

    Checking and adding the brake fluid
    ■ Checking fluid level The brake fluid level should be between the "MAX" and "MIN" lines on the tank. ■ Adding fluid 1. Slide and lift up the rubber strip to partly remove it as shown. 2. Disconnect the claws and remove the service cover. 3. Remove the reservoir cap. 4. Add brake fluid slowl ...