No Sound From One Of The Speakers

No Sound From One Of The Speakers

Fault symptoms
No sound from one of the speakers.

Probable cause of fault
Break in a speaker coil.
Break in a speaker circuit or in the connection between the main unit and the amplifier.

Diagnostic help
Speaker test: 4 channels.
Start the speaker test by holding down the RADIO
button when the main unit is switched on.

Important
Check the balance and fader control settings.

Check wiring harness
Jiggle the wiring harness at several points and in different directions to reveal intermittent breaks and short-circuits in the leads. Observe the multimeter, test lamp or diagnostic instrument during the test.





Diagnostic Procedure

1 Check the amplifier connections to the speakers
- Turn the ignition switch to OFF.
- Remove the ignition key from the lock.
- Unplug the audio amplifier's 39-pin connector.
- Take a resistance reading across the pins:
Resistance values according to table below






- Take a resistance reading across the pin concerned and a good grounding point.
All resistance values should be infinite.

Test results OK?
YES
Continue with point 2.
NO
Repair or replace the lead or faulty speaker concerned
Continue with point 3, Final Check.






2 Checking the main unit's low-level outputs
- Connect a speaker (front centre speaker) to the low-level output concerned on the amplifier's female connector.
- Listen to the speaker at medium sound level.
Sound should be coming from the speaker.

Test results OK?
YES
See Fault diagnosis, general. "Before changing a control module."
If necessary replace amplifier.
Continue with point 3, Final Check.
NO
Repair or replace lead concerned.
Continue with point 3, Final Check.






3 Final check
- Carry out a function check.
- Evaluate the function check.
- Check that the symptom has not recurred.

Has the symptom recurred?
YES
Continue with Fault diagnosis, general, "Before changing a control module." Before Changing A Control Module
NO
The steps taken to rectify the fault were correct.