Nokia RM-57 Service Manual page 323

RM-57/58
Camera Module Troubleshooting Nokia Customer Care
Figure 91 Mechanical construction of the flash LED module
The flash LED module as a component is not a repairable part, i.e. components / parts in the module cannot be
changed. Only cleaning dust from the lens is allowed; use clean compressed air.
The main parts of the module are:
• Housing, which is glued to the PWB
• Lens area (round area on top of the housing with circle patterns)
• LED chip (yellow chip inside the housing), which is soldered to the PWB
• ESD protection diode (black passive component inside the housing), which is soldered to the PWB
• PWB
• Contact pads
• Laser marked serial number
The flash LED is fixed to the phone mechanics with special clips. The contacts to the main PWB are formed by
using spring connectors.
Analysing image quality
Possible faults in image quality
When checking for possible errors in the flash functionality, knowing what error is suspected will significantly
help the testing by narrowing down the amount of test cases. The following types of image quality problems
may be expected to appear:
• LED module is not flashing at all
• Image colours are not good
• Flash power is weak
Testing flash module functionality
For testing the module's overall functionality, take an image with the flash and monitor at same time whether
the LED module flashes.
To do this test always use the FORCED FLASH mode in the phone, not the AUTOMATIC mode. The FORCED FLASH
mode enforces the LED module to flash, even if there is some ambient light in present.
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