Microphone in phone handset will not pick up voices

Hi @buzzzee ,

Just double checking. Have you checked that the mute button has not been pressed? (the antenna indicator should be blinking if it has). To 'un-mute' press the mute button again.

It may be difficult to fix if the microphone is actually faulty. Getting the correct replacement part may be the problem.

Here is a link to the ifixit GE 27990G3 Cordless Phone Teardown guide.

It is useful as it shows how to dis-assemble the phone so that you can check for 3 possible causes of the problem.

1. The voice inlet holes may be blocked preventing the sound being picked up by the microphone.

(click on image to enlarge for better viewing)

2. The electret microphone, (shown in Step.11 of the guide) may have become detached from the systemboard.

3. The headset jack may be faulty.

This is conjecture on my part as I don't know how it is wired in. It may be the type of connector that has internal sets of contacts that physically break the circuit away from the phone's internal receiver and microphone and transfer it to the external headset when it is plugged in. You can try plugging in and out a 4 ring connector plug a few times and check if the phone's internal microphone now works. if so it may have temporarily fixed the problem and pointed to where the problem is.

If all appears OK then the microphone may have failed or there is a problem further into the systemboard.

You can try to test if the voice transmission circuit is OK by inserting a set of headphones with the microphone attachment into the headset jack on the side of the phone and check if you can be heard OK on a call. This may not work as you may have to have the appropriate headset connection and there are two popular methods of connection. The microphone connection is reversed between the two methods so it may depend which way the phone and headset are wired as to whether this will work.

(click on image to enlarge for better viewing)