Left Front output is not working, JBL Marine MA4505

[jfxwave]

I tested everything that might be wrong but everything is prefect. All other channels work great, even the sub channel.

Does anyone know what i might of missed checking or any other help will be appreciated!
I uploaded some pictures in case you need them.

 

[Perry Babin]

Have you tried operating all of the pots and switches through their entire range with a signal source connected and a speaker connected to the dead channel to see if the channel ever produced any sort of sound (even if it was just static/noise)?

Did you unplug and reseat the preamp board to see if it may have a bad connection?

 

[jfxwave]

Yes, Thats the first thing did and not the smallest sound, no click or nothing.
I think there is a open circuit on the left channel on the output side. I tried to follow the trace but that damn resin or whatever they use on marine amplifiers make my probes hard to make a good contact.

 

[Perry Babin]

Clip the scope probe to a jewelers screwdriver and scrape through the coating with the screwdriver to make the connection.

Map out all channels (feeding one channel at a time) if the board isn't marked to find where you should see the missing signal.