HP PL4260N Service Manual page 65

Failure type
Source: DIGITAL TV
Description: NO SIGNAL/Menu displays only, and
no video picture, other source is OK.
Inspection items
1 Change P. Mode to Standard Mode and check
the signal cable.
2 Check whether there is signal input to the RF
terminal.
3 Open the back cover.
4 Check the power connector XP004 and pin
#TAB/N801=+5V,#TAB/N802=+2.5V,#TAB/N
803=+3.3V, #TAB/N804=+1.2V,
#TAB/N805=+9V, #TAB/N806=+5V.
5 Check whether the voltage of R109 is 0V.
6 Check whether there is correct signal on pin
#10(TS1_START)/#11(TS1_VAL)/
#13_ (TS1_CLK)/#15(TS1_D0) of
CON28 on MB.
7 Check whether there is correct signal on pin
#1/#2/#3/#4 of RN26 on BM.
8 Check whether there is correct signal on pin that
close U9 of R948/R949/R138/
R2290/R2291 on BM.
9 Replace the MB if the other steps are correct.
Item
Normal operation [source audio]
Description
There is sound from speakers when the current
source has picture signal and audio signal, and the
volume over the 20 level.
Picture
CON28 connects MB and TB.
Remarks
X-TAL:digital:low. Analog: high.
pin of R109: X-TAL switch
Picture
Remarks
There is no sound when the "NO SIGNAL" indicator
displays onscreen from speakers even when the volume is at
the 100 level.
HP High-Definition Plasma TV Service Manual PL4260N, PL5060N
59