Hi
Not much technical on sky digibox  on the net but hears a start all these fault are based on Pace hope it helps you.
 
 
Stuck in standby
Nature of problem.
When the unit powers up, the red light comes on but, even after a minute, it will not come out of standby
For checks to be carried out, see below
 
(1)
Pins 3 and 4 of CON2O for 5V and 3V3 respectively If NO = Fault associated with the PSU
If OK goto 2
(2)
MEMDATA activity on pin 11 of U272 or the pad if IC not fitted (refer to WF 1) If NO = X370 is producing 27 MHz (pin 6, U370) If YES goto 2a If NO Fault = VCXO cct
(2a) notrst is correct 3 3 V (pin 116, U300) If NO = Housekeeping cct
If OK goto 3
(3)
Activity on pin 73 of U700 (refer to WF 2) = WF 2
If YES goto 5 If NO goto 4
(4)
X700 for 29MHz on pins 66 and 67 of U700 If NO = Check signal on C702 (294 MHz, 26 Vp-p sat on 400 mV) and C703 (29.4 MHz,1 9Vp-p saton 600 my) If low, change U700 and parts in Modem Spares Kit
If YES goto 5
(5)
I2C activity on pin 13 (refer to WF3) and pin 3 (refer to WF4) of U211 If NO = Components on I2C bus
(6)
If revision B1 PCB, suspect ZIF tuner (Note remote command LED usually still flashes when a key on the remote is pressed
(7)
GIVE UP
 
 
 
Primary symptoms
PCB rev.
Secondary symptoms
Checks to be made
Components to be replaced
 
 
Intermittently stuck in standby
A2-B1
I2C lines low (not 3v3)
Check for water ingress around the modulator can Rust forming on the PCB can cause a partial short between the I2CBus and ground (There are two pads on the PCB in front of the modulator can, behind L690, which are the I2C data bus ) Clean the affected area with PCB cleaning-fluid
 
Intermittently stuck in standby
A2-A3
U386
 
Stuck in standby
A2-A7
No 10 MHz
X401
 
Stuck in standby
A2-B1
No 29 MHz reference
U700
 
Stuck in standby
A2-B1
remote command LED flashes when a remote control key is pressed
U7002 and U7006
 
Stuck in standby
B1
remote command LED flashes when a remote control key is pressed
ZIF tuner
 
Stuck in standby
A2-B1
Low voltage readings on various PSU rails
Check for short-circuit on U4
 
Stuck in standby
A2-B1
SDRAM clock OK l2C held at 3V3, with occasional small burst ot data
U900 and U901
 
Stuck in standby
5512 [Al]
12C data present but not correct (too much activity)
ZIF tuner
 
No teletext operation
A2-Bl
Control line ttxtrequest is OK, but ttxtdata is held high
U300
 
No UHF channel 69
A2-B1
Voltage reading on D640 higher than normal over the range of UHF channels
D640
 
No IR operation via RF2
A2-B1
Remote IR signal is OK going into Q605 IR works OK via the front panel
Check the 5V output of Reg 1, it needs to be very accurate
Reg 1
 
No IR operation via RF2
A2-B1
8V signal output from RF2, but no operation
Q603 and Q604
 
No IR operation via RF2
A2-B1
No 8V supply, or supply is low
R70
 
No IR operation via RF2
A2-B1
No 8V supply, or supply is incorrect
D53
 
Crackling on audio via Scart
A2-B1
Check for dry joints on R955 and R997. Also, check for dry joints around U903, U907 and U908
 
No audio or crackling
A2-B1
No PCMDATA on pin 41 of U320
U320
 
 
Crackling audio
A2-A4
0550 very hot 0551 pulling down 5V output
 
U551
No audio via
Scart
(OK via RF)
A2-Bl
Check for short-circuit across C3012
 
No audio
A2-Bl
No signals at inputs of U551
U320
 
Tone superimposed on audio
A2-Bl
Tone is being generated by G729 chip and added to the audio signal
 
03002
High pitch whistle on audio
A2-Bl
U320
 
No audio
A2-Bi
video OK
Check for dry joints around
U551
 
No audio on modulator
A2-B1
Audio OK on Scart
U905
 
Audio disappears or distorts when STB is warm
A2-B1
Fault in 0729 operation
U3002
 
LNB supply incorrect
A2-Bl
Both H and V measure low
D1O5
 
Distorted audio
5512 [A1}
Sounds like a Dalek'
BGA chip (0300)
 
No horizontal channels
A2-Bl
Vertical channels OK
U103 and Q103
 
No satellite signal
A2-A7
C433 and C434
 
No satellite signal
A2-A7
Voltage on pin 3 of U451 high, pin 50 is OV
Tuner
 
No satellite signal
A2-A7
Signal-strength reading is low Signal-quality reading is fluctuating
Tuner
 
No satellite signal on some channels
A2-A7
Low- and high-frequency transponders are missing Middle ones are OK
Check D405 30V Zener to see whether it is pulling down the tuner volts
D405
 
No TV listings
A2-Bl
U32O
 
No TV listings
A2-B1
STB works OK apart from lack of TV listings
07002 and U7006
 
No TV listings, no video or audio
A2-Bl
Check signals from front end on multiplex outputs (U151,Ul53andUl55) If signals are OK, change U300 If the signal is not correct, the fault lies in the front-end circuit
 
Fine, colored lines on picture
A2-Bl
U500
 
Small green squares or small block of lines on screen
A2-Bi
Some channels are worse than others
U321 and LJ322
 
Blocks on menu
A2-B1
Remote function may lock up Picture OK
U321 and U322
 
No RF output
A2-Bl
Check for 4 MHz (X640) on crystal side of C653
 
Black-and-white rolling picture on channels 68 and 69
A2-Bi
OK on other RF channels
C650 and C651
 
Picture and audio freezing intermittently
A2-A7
U404
 
Poor picture on AV and RF
A2-B1
Pink, snowy picture Sound OK
U321 and U322
 
Picture is black and white
A2-Bi
X370 27 MF-lz reference running at wrong frequency
C370
 
Blank screen
A2-Bi
Audio OK
Check for dry joints around U900 and U901
 
Blue screen, no audio
A2-B1
No audio output from U901
U900 and U901
 
Intermittent picture break-up
A2-B1
Menus showing blocks and bars
U321 and U322
 
Intermittent picture break-up
A2-Bi
Searching tor TV listings on weak signal
R116, R117, C107 and D109
 
Intermittent picture freezing
A2-A7
Errors on notfecfail
U403
 
Intermittent I picture freezing
A2-A7
Check pin 22 of U404 for
55 MHz and pin 1 of U402
for stable 5V
U404
 
At System Test screen, a message is displayed Telephone line not connected'
A2-B1
STB cannot see telephone voltage
U853, U854 and 0854
 
No switching on Start pin 16
A2-Bi
No RGB operation
Q902 and Q903
 
No switching on Scart pin 8
A2-B1
No widescreen switching
Q904
 
Not reading card
A2-A3
Only free-to-air channels available
R391
 
No 22 kHz tone on horizontal polarity
A2-B1
OK on vertical channels
Q103
 
On-screen message indicates problem with viewing card
A2-B1
Check 4 5 MHz 5 V p-p waveform on pin 15 of U1100
If not present, check that input on pin 24 is 45 MHz 4 5 V p-p If OK, change U1100
 
Will not dial out
A2-B1
System test OK
Q0850
 
Displays purple screen
A2-B1
No SDRAM clock at pin 35 on U321 and U322
U7200
 
Fails to go off hook'
A2-B1
D854
 
Sky menus displayed in wrong colour
A2-B1
Video and audio OK
U320
 
Slow to boot up
A2-B1
Modem IC not running
U700
 
Access to Open....
interactive services is suddenly lost
5512 {A1)
On-screen display reverts to the main Sky Guide Interactive menu
U300
 
ERR on front-panel display
X102 on front panel
 
ERR on front-panel display
Intermittently OK I2C incorrect
C305
 
No channels viewable
Scans OK If powered down, then powered back up, Welcome screen is displayed
Check U254 for dry joints
 
Will not tune
U300
 
Will not switch on
Check U300 for dry joints
 
No audio
Check that digital audio signals are present from U320 on pins 1, 2, 41 and 42. If they are not present, suspect U320 If they are present, proceed to check from the audio DAC (Digital-to Analogue) onwards.
 
Modem faulty
Replace the modem IC, U700 (Pace Part No 265-230A2B1) Also, replace all related components, using the Modem Spares Kit (Pace Part No. 903-001675 1)
   
   

 

SECONDARY PSU

 

 
Will not power up (dead)
Check the resistance of the 3V3 and 5V with respect to ground. If they both measure below 1K, suspect multiple failures (usually caused by a lightning strike) If this is the case, a repair is normally uneconomical.
 
 
No short-circuit, but still dead
Check to see if the power lines are pulsing, which would indicate a tripping PSU Note that the PSU may trip very quickly and that this tripping may not be audible. Suspect secondary diodes and Dl If there are no supplies at all, suspect FS1, U1, U2, U3, D45 and C3.
The best place to check the secondary supplies is on C0N20 C0N20 is a series of five pads situated at the front right-hand side of the PCB Figure 2, below~ shows which pad is associated with which rail
 
 
CON20=
33v 16v 5v 3v3 0v
o   o   o  o   o
33V  high
16V  high
5V   1k2
3V3  1k  
 
SECONDARY PSU RAILS
 
Diode Voltage
 
D20  (+) 3.3V
Components that use the supply:
U151 to U155, U200, U203 to U206, U208, U210, U271 to
U274, U300, U305, U320, U321, U322, U370, U386, U403,
U500, U600, U601, U700, U805, 0854, U10O0, U1100,
U110l, U7002, U7006, U7200, U7202, U7204, U7206
 
D25=(-)8v
 
D30
(+) 5.7V = U156, U402 Also used to generate 5V and 5VF
(+) 5V = U156, U211, U350, U388, U404, U702, U703, U802, U902
(+) 5VF = U451
(+) 5VG = U3001 (5VG is taken from the 5V rail via L3000)
(+) 5VA = U551 (taken from the (+) 8V by U550)
 
D35
(+) 8V = U550, U602, U900, 0901
(+) 8VA = 11903, U905, U907, 0908 (taken from (+) 8V)
 
D38
(+) 16V = Used for LNB switching
 
D45
(+) 20V = Used for LNB switching
 
D50
(+) 33V = U401, TUN400
 
 
D51
(+) 27V = U103
(+) 24V = U400 (taken from the (+) 33V rail via D404)
 
 
 

Free to Air (FTA) Channels on Sky Digital (September 2002)
Channels marked * require the BBC/ITV/FTA viewing card.

Entertainment

101 BBC 1*
102 BBC 2*
103 ITV 1 LOCAL*    (+ 16 Regional Variations*)
104 Channel 4*
105 Channel 5*
160 BBC Choice*
161 BBC Four*
181 Travel
193 Channel Health
202 Life TV
208 Showcase
220 Fashion TV
223 Games Network
229 You TV
235 Avago
238 Ben

Movies

327 TCM (Movies)

Sports

410 Racing Channel (Sometimes)
414 Go Barking Mad
416 Motors TV
422 Extreme Sports

Music

455 Vibe TV
464 D-Classics TV

News & Documentaries

501 Sky News
507 BBC News 24*
508 BBC Parliament
513 CNN
519 S4C2
525 ITN News
528 EuroNews
576 einstein.tv


Other

960 BBC 2 Scotland*
961 BBC 2 Wales*
962 BBC 2 N. I.*
996 Audio Ch. Line-up

Children

603 Boomerang
621 CBBC*
622 Cbeebies*

Specialist

630 QVC
631 TV Travel Shop
632 TV Travel Shop 2
634 PIN
635 Ideal World
636 Screenshop
637 Shop America
638 Travel Dea
639 Simply Shop
640 Best Direct
641 Simply Health
642 Simply Jewel
643 Simply Holidays
644 HSE Shopping
645 Simply Shop+
646 TV Warehouse
647 Bid-up.tv
648 Thomas Cook
649 Telsell
650 Lets Go Shop+
651 Auction World
652 Shop On T V
653 Simply Home
654 Simply Music
655 Thane Direct
656 Smart Shop
657 Shop Aid TV
658 Shopping Genie
659 Shop 24/7
660 Stop + Shop
662 Job Shop
671 God Channel
672 God Revivall
674 TBN Europe
683 TV Jobshop
684 Community
685 Dating Channe
801 B4U Music
805 PCNE Chinese
806 Al Jazeera
807 Mta-Muslim TV
817 South For You

Radio Channels

851 BBC Radio 1
852 BBC Radio 2
853 BBC Radio 3
854 BBC Radio 4 FM
855 BBC Radio 5 Live*
856 Classic FM
857 Virgin Radio
859 Classic Gold
860 The Mix
861 Planet Rock
862 Core
863 Capital Gold
864 XFM
865 BBC World Service
866 BBC R. Scotland
867 BBC R. Wales
868 BBC R. Ulster
869 BBC Asian Net.
870 BBC Radio 4 LW
871 youthfm.com
872 WRN EuroMax
873 Premier
874 Heart
875 UCB Europe
876 Cross Rhythm
877 One Word
878 ITN Radio
879 Solar Radio
880 Panjab Radio
881 Storm Live
882 Prime Time
883 Sunrise Radio
884 Talk Gospel
885 Total Rock
886 UCB Inspirational
887 The Storm
888 TWR
889 LBH Radio
890 UCB Bible
891 UCB Talk
892 RTE Radio 1
893 Asian Air
895 Club Asia
896 Real Radio
897 EWTN
900 Sukh Sagar
901 Asian Gold
902 BBC WS Extra
907 BBC 5 L Sport X*
908 Gaydar Radio
910 Team Talk 252
911 BBC 6 Music
912 Purple Radio
913 APNA Radio
914 2 FM
915 Lyric FM
916 RnaG
917 Jazz Fm
918 Akash Radio