Some of camera hardware problems such as, camera on standby mode, a blank or black display appears when the camera is open.
This solution can be used for tracing the line paths and for easy locating the camera circuit components that is connected within the camera circuit. however; this repair guide can only be used if the main camera module already been check, test or already installed a new replacement camera module but the problem still exists.
Nokia 5800 xpressmusic camera repair solution
Camera failure repair hints:
Checking the firmware and replacing a new camera module replacement may the first step to fix camera failures, the next thing you could do next is by checking the desired supply voltage that feeds to the camera module before trying to touch any other components within the circuit.
In this circuit there are three supply voltage that feeds to the camera module.
1. Vbat - a supply voltage from the cell phones battery 3.7 DC voltage
2. Vcam_1.8 - camera voltage 1.8 DC voltage
3. Vcam_2.8 - camera voltage 2.8 DC voltage
If one of these three voltages is missing the camera will not be able to function.
The Vcam or camera supply voltages is feeds from a DC to DC converter SMD IC, this smd ic converts the battery voltage to a desired certain voltages such us 1.8 volts and 2.8 volts.
You may easily check each of these voltages by locating a certain components parts like filter coils (power inductors) and smt capacitors, in which this particular voltage flow across to it.
Make a continuity check on all data lines paths from a particular components to each of the camera module terminal pins. Next have all corresponding smd components be check or replace like the filter coil, resistors and capacitors.
Reworking or reballing the solder balls of the camera chip or replacing it may possibly fix, if all of the above does not solve the problem.