View Single Post
Old 05-05-2011, 15:15   #12 (permalink)
aZimBahar
Product Manager
 
aZimBahar's Avatar
 
Join Date: Dec 2009
Location: CEO.of.ROMDevelopers
Age: 32
Posts: 16,030
Member: 1174508
Status: Offline
Sonork: 100.1593820
Thanks Meter: 11,979
Donate money to this user

Hints in troubleshooting keypad LED light failure problem:
1. Check the keypad matrix flex assembly, clean it if oxidized. replace the whole flex board if severely damaged.
2. Check each of the white LED light bulbs using a multimeter set to X1.
3. Check and trace the positive (LED+) and negative (LED-) supply voltage.
3. The negative supply(LED-) of the keypad LED is feed from the PEARLJ IC.
4. The components such as the transistors, inductor coil and diode will only be check if also the Display backlight LED failed or show a dark screen
  Reply With Quote
The Following 3 Users Say Thank You to aZimBahar For This Useful Post:
Show/Hide list of the thanked
 
Page generated in 0.07885 seconds with 7 queries