Battery not charging after dock connector replacement, iPhone4

Hi all,

My iPhone4 suffered mild water damage (water damage indicator not triggered) and misbehaved on that day. So I turned off the device and put it in a bag of rice for almost a month. When I eventually took it out, it was almost as good as before except for some weird quirks. One of them is the audio control. I can listen to music using headphone jack, but cannot listen through speakers. I see some corrosion on my dock charger. I am still able to connect to iTunes and charge using cables. I know my speakers works as I am able to hear the phone ring. However increasing and decreasing volume shows only the ringer icon with no bars underneath. Upon searching online I found out (in another thread on this website) that the phone could believe it is connected to some kind of docking device. I tried cleaning the dock using a brush, but no use.

So I took some time and replaced the dock connector. After I finished re-assembly and turned on my phone, I noticed that my audio issue is resolved. I am now able to adjust volume using the buttons and can see the volume level (bars) go up or down. Also I can listen to the music from the speakers. However it is not syncing/charging.

Logically this can mean two likely issues (1) I have a faulty dock connector (2) I messed up my battery during disassembly (The battery flex connector was too tight and while I was removing it with the plastic spudger, it popped up suddenly and caused my spudger to go in a tad too far. My flex cable did not rip off and I didnt see any broken pieces, so I assumed nothing bad happened, but I am not sure).

If my dock connector is faulty, then my audio problem should not have been resolved correct? Because the logic board would not know that I have a new clean dock connector installed. This is what I am assuming, I am not sure. If some one could clarify this assumption, that would be great.

Of course this leads me to believe that I messed up my battery. I don't have a spare battery to try out, need to buy one.

Meanwhile I have a spare dock connector to try out. I am not sure if that is going to help. I am hoping someone in this community and say that it is obviously one problem or the other. If not, I will go through the dock connector replacement again and hope it all works out.

Also does anyone know if I can just plug in the new dock connector to the logic board and try syncing (of course with the battery connected) while my phone is still open (and the other components have not been removed)? This would seem like a nice quick test prior to going through the full repair. I am not sure if this is safe.

Thank you very much