before proceeding to this steps make sure that you already done software calibration and the basic steps on how to check audio circuit components which I already explained here:
How Audio Codec do on Mouthpiece, Earpiece, IHF speaker or Buzzer on mobile phone circuits
How to Test Mobile phone Speaker,Buzzer or Ringer
Okay, remove the shield shown the picture below for it is where the audio circuit components of Nokia 5800 xpressmusic is located or being mounted.
Now, the Nokia 5800 xpressmusic schematic diagram shown below an audio circuit which is feed from a the audio codec IC (not shown on the picture) Unlike most Nokia Audio circuits in some models, the 5800 xpressmusic has an audio amplifier chips or IC that amplifies the audio signal before it goes through the IHF ( Intermediate High Frequency) Speaker. This chip also designed to controls the audio signal's volume. It has two channels, the left and right channel, which is so-called stereo type amplifier.
The components layout and connection path lines with each certain components from the schematic diagram is in the picture below. The chips layout which I in-lined with colors indicates each certain components that are being shown or listed from the schematic diagram in the above image.
You can use this image to trace lines and faulty components by referring each component's desired values from an aide of schematic diagram above..
Here's a simple tricks on how to troubleshoot with an aide of the picture below.
Assuming that we already restore or flash it with its original or desired flash firmware and been already test the speaker working fine, but the problem still exist,
follow this some steps:
1. Determine which channel or speaker got no sound output. the left channel is where I colored "pink" and the right channel is colored "red". if both channel speaker got no sounds output, preferably the problem lies from the audio codec chip or from the audio amplifier chip, but don't rush on there that quickly, it's unsure yet and ain't that easy to determine which one causes the problem. Always start from outer layer of the whole circuit,
what I mean is that check all components from the outside most components before going deep to the inner parts.
2. Check the following output filter coils, the value of this said coils are too small enough and quite possible easy to break and typically designed for the speakers protection. Replace if found busted.
3. Check and test the two other output filter coils in each designated lines. Replace if busted.
4. Check or rather replace the inputs capacitors on each channel, or by only which channel have a problem.
5. In this stage considering that all of the above is already done and those components were all fine and stable. this where we suspect the audio codec chip or the audio amplifier chip causes the problem.
The audio amplifier chip will take to test first for it is an outer components rather than the audio codec chip.
6. Reheat or rework the chips or replace if possible that is the quickest method.
BUT BEFORE THAT, in working on Integrated Circuit or chip, always check first if there is a voltage supply on it and or properly connected to ground lines. In this manner you are checking and testing the chip's itself, ob-course chips won't work without a proper power supply on it.
By an aide of the picture above trace the power supply voltage of the chip, it is range around 3.7 VDC which directly a voltage from the phone's battery.
8. The last stage is working on the Audio codec chip, in this stage needs extra care for an audio codec circuit is also combined with power management circuit. This what called the power IC.
Reheat, rework or reball it, is the last stage of whole troubleshooting procedure.
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