Toyota Corolla Repair Manual: 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
No sound is heard from speaker in all modes
Wiring diagram
Inspection procedure
1 Check lcd (liquid crystal display) for lighting
Lcd illumination check
turn the ignition switch acc.
Turn the radio receiver assembl ...
Radio broadcast cannot be received (bad reception)
Inspection procedure
1 Check if radio auto–search functions properly
Check if the radio auto–search functions properly.
Perform the auto–search of the radio and check that it function ...
Other materials:
Instrument panel/meter
Preparation
Sst
Recomended tools
Equipment
Seat
Preparation
Equipment
Theft deterrent & door lock
Preparation
Recomended tools
...
Checking and replacing fuses
If any of the electrical components do not operate, a fuse may have blown.
If this happens, check and replace the fuses as necessary.
1 Turn the engine switch off.
2 Open the fuse box cover.
► Engine compartment
Push the tab in and lift the lid off.
► Under the driver’s side ins ...
On–vehicle inspection
1. Check battery electrolyte level
Check the electrolyte quantity of each cell (maintenance–free battery).
If under the lower level, replace the battery (or add distilled
water if possible) and check the charging
system.
check the electrolyte quantity of each cell (e ...