Sprint Nextel T600 - Manual (Page 5)

Trouble Shooting Guide, Electrical
4/00021-2/FEA 209 544/74 A
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Sony Ericsson Mobile Communications AB
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4 Display/Illumination Problems
• Make visual check to ensure that the elastomer is properly in place in its housing in
Display assy (Fig. 4-1). Also clean the Display pads from the circuit board if necessary.
• Replace the display according to the Working Instruction, Mechanical.
• In Display/Illumination problems make visual check to ensure that the White colour
display LEDs (4 pieces) (Fig. 4-2) and Blue colour keymat LEDs (6 pieces) (Fig. 4-3)
are properly in place. Check also for the incorrect soldering of the LEDs. Re-solder it if
needed.
• If few but not all of the LEDs aren’t lit, replace broken ones according to the Working
Instruction, Electrical.
• If none of the LEDs are lit, proceed according to following:
1. Check White colour display LEDs and Blue colour keymat LEDs
2. Measure resistance of the LEDs.
• If the resistance is approx. 0 Ohms, there’s a short circuit in at least one of the
LEDs. Remove them one at a time and measure the resistance after each
removal. When the resistance increases the faulty LED has been removed.
If the fault still remains, handle the unit according to local directives.
Figure 4-1
Figure 4-2