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17pw26-4



bubba21
New User

Aug 13, 2015, 12:49 PM


Views: 6073
17pw26-4
hi everyone have a toshiba 40bv700b tv with no power i orderd another power board the same and no power checked the power cable and its ok took this apart some time ago and just got round to seeing to it now, so i think i have missed someting regarding a cable, so if anyone knows is there a cable that goes from the PL801 yellow plug located (beside the led out cable) to the PL804 which is a white plug there is no cables in here and just wanted to know should there be thanks



jts1957
Veteran


Aug 13, 2015, 5:10 PM


Views: 6055
Re: [bubba21] 17pw26-4
PL801 & PL802 are both for inverter(s) to run the CCFL back lights (sorry, NO LEDs for backlighting this puppy). PL804 would to to someplace that requires 12 volts and/or 5 volts. Some sets don't use all connectors.


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bubba21
New User

Aug 14, 2015, 9:05 AM


Views: 6047
Re: [jts1957] 17pw26-4
thakyou for the reply i could not remeber if i had removed a cable or not bought a working power board so need to check the signal board, here goes fault finding i now know at least that the power board is ok i just need to see if the signal board is getting the correct voltage as there is no standby LED on thankyou again


bubba21
New User

Aug 14, 2015, 12:35 PM


Views: 6044
Re: [jts1957] 17pw26-4
could the rocker switch be at fault when i meter it when switched on it reads 88v then climes to 224v, but i can not get any low voltage reading on any of the pins going to the signal board no 24v 12v 3v or 5v??


jts1957
Veteran


Aug 14, 2015, 4:15 PM


Views: 6041
Re: [bubba21] 17pw26-4
Test rocker switch: UNPLUG TV from mains - Put DVM on a low ohms range - connect across rocker switch contacts. In one position the rocker should read zero, in the other position rocker will read higher, maybe even over range.
While you have Meter on ohms, measure across the two contacts of F800 and see if it read zero.


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bubba21
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Aug 14, 2015, 11:02 PM


Views: 6030
Re: [jts1957] 17pw26-4
ok just got in from work thanks again for replying took the switch off and checked the power board F800 pins and reads zero. I have taken the rocker switch off to test my lowest reading in ohms on my multimeter is 200 then goes up to 2k then 20k then 200k then 2m, so i put it on 200 and throw the swithch it quickly starts off at between 33 and 94 then levels out at 00.9 then flickers between 01.0 and 00.9switch it off and nothing but when switched back on it just does the same, is this normal thanks again


jts1957
Veteran


Aug 14, 2015, 11:46 PM


Views: 6028
Re: [bubba21] 17pw26-4
Switch is Good. Fuse is good.

Meter on ACV. Plug set in and switch ON.
Measure AC Mains voltage: PL809: pin 1 gets red lead, at the same time, pin 2 gets black lead. DO NOT LET THEM SHORT TOGETHER! You won't like it if you do. (You haven't taken the welding course yet.) IF not there stop & report, IF present there try to measure for SAME mains voltage across the two AC pins of D800 (D800 may have these four markings: ~ - + ~. Measure with one meter lead to one '~' and the other meter lead to the other '~'.


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bubba21
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Aug 15, 2015, 12:13 AM


Views: 6024
Re: [jts1957] 17pw26-4
ac on PL809 IS 242V when switched on at mains PL815 (PL800??) when rocker switch is thrown is 90v 5 seconds jumps to 145v then eventurally levels out at 220v can not find PL800 i am asuming this is where the rocker switch plug goes into is PL815 on my board ??


jts1957
Veteran


Aug 15, 2015, 12:27 AM


Views: 6020
Re: [bubba21] 17pw26-4
PL809 DOES go to your power cord, then to the wall receptacle, Yes? IF so then AC242 should be there at Mains voltage as long as set remains plugged in, regardless of other factors.

What kind of rocker switch. How many terminals? Where is it plugged in? Is it Mains 'vacation' switch, Mains 'On-OFF' or something else?

PL800 is D800 the Bridge rectifier in the set.


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Location: Far, Far Away

(This post was edited by jts1957 on Aug 15, 2015, 12:28 AM)


bubba21
New User

Aug 15, 2015, 1:00 AM


Views: 6017
Re: [jts1957] 17pw26-4
yes 242 volts at PL809 The rocker switch is labeld on off this goes to the power board. mains plug PL809 is on one side, round fuse in the middle, and the PL815 2 pin socket on the other side, this is where the rocker switch(on off) plugs into (mains on off) also found D800 the Bridge rectifier one side is plus the other side is minus 2 sqiggly lines in the middle


(This post was edited by bubba21 on Aug 15, 2015, 1:24 AM)


jts1957
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Aug 15, 2015, 1:56 AM


Views: 6008
Re: [bubba21] 17pw26-4
2nd try: Measure AC Mains voltage: PL809: pin 1 gets red lead, at the same time, pin 2 gets black lead. DO NOT LET THEM SHORT TOGETHER! You won't like it if you do. (You haven't taken the welding course yet.) IF NOT there stop & report, IF present there try to measure for SAME mains voltage across the two AC pins of D800 (D800 may have these four markings: ~ - + ~. Measure with one meter lead to one '~' and the other meter lead to the other '~'.


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Location: Far, Far Away


bubba21
New User

Aug 15, 2015, 2:08 AM


Views: 6006
Re: [jts1957] 17pw26-4
will measure in the morning my eyes are closing and i might just get a welding course i am asuming this is to see weather its turning from ac to dc on the diodes??


jts1957
Veteran


Aug 15, 2015, 2:35 AM


Views: 6003
Re: [bubba21] 17pw26-4
Quote
1) here goes fault finding i now know at least that the power board is ok
Quote
2) i can not get any low voltage reading on any of the pins going to the signal board no 24v 12v 3v or 5v??
1) IF the Power board is/was OK, you will get those voltages (At least the standby voltage.)

2) How coincidental ... those just happen to come from the power board.


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Location: Far, Far Away

(This post was edited by jts1957 on Aug 15, 2015, 2:39 AM)


bubba21
New User

Aug 15, 2015, 9:43 AM


Views: 5997
Re: [jts1957] 17pw26-4
ok DC is reading 326v and AC is reading 238v when unpluged the bridge rectifier reads 0 one way and when the brobes are reversed on the rectifer they read .5 the other way, does this sound right?


(This post was edited by bubba21 on Aug 15, 2015, 9:44 AM)


bubba21
New User

Aug 15, 2015, 11:38 AM


Views: 5989
Re: [bubba21] 17pw26-4
oo thats weird i put my old board in and got all the voltages +5 on pin 14 3.3v on pin 16 3v on pins 18 20 22 and 24v on pin 26 pluged it into the signal board and the white led stndby light came on but then tried to turn the tv on it tried to switch on then went off so i have metered the pins again and only the 5v pin is reading can not get any voltage reading on others and no standby lights are on, i think i will be sending the board i bought back as the model no is 17pw26-5 and can not get a 5v standby on it, Was told this was compatible with my tv and the board had been removed from a tv where the issue Was not the power board hmmmmmmm


(This post was edited by bubba21 on Aug 15, 2015, 11:44 AM)


jts1957
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Aug 15, 2015, 3:22 PM


Views: 5981
Re: [bubba21] 17pw26-4
Quote
when unpluged the bridge rectifier reads 0 one way and when the brobes are reversed on the rectifer they read .5 the other way, does this sound right?
Depends on where Function on your meter was set at that time.

3.3v standby & 5v standby should be present ALL the time TV is plugged into Mains.


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Location: Far, Far Away

(This post was edited by jts1957 on Aug 15, 2015, 5:12 PM)


bubba21
New User

Aug 15, 2015, 4:34 PM


Views: 5977
Re: [jts1957] 17pw26-4
meter set to diode symbol when unpluged. With the meter set to 600 DC and the tv plugged in and turned on i get 326 volts reading on + - and get 238 on AC ~~ of the rectifier


(This post was edited by bubba21 on Aug 15, 2015, 4:51 PM)


jts1957
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Aug 15, 2015, 4:51 PM


Views: 5968
Re: [bubba21] 17pw26-4


Quote
and get 238 on AC ~~ of the rectifier.
Hopefully you switch meter to 'AC' for that one.


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Location: Far, Far Away


bubba21
New User

Aug 15, 2015, 4:54 PM


Views: 5966
Re: [jts1957] 17pw26-4
correct no loud pops or bangs or shocks yet, so with the red probe on the anode and the black probe on the cathode of the rectifier and the power board unplugged i get a negative reading, keeping the red probe on the anode and moving along from the cathode each leg is 0, so when i switch the red probe to the cathode and the black probe to the anode i get a 0.540 reading on all legs of the rectifier, does that make sense??


(This post was edited by bubba21 on Aug 15, 2015, 5:09 PM)


jts1957
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Aug 15, 2015, 5:20 PM


Views: 5952
Re: [bubba21] 17pw26-4
You're neglecting to say how meter is set.

See my bold edit above.

Also: until BOTH the 'vacation' rocker switch AND the relay turns ON there will be ONLY Standby voltages present.


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bubba21
New User

Aug 15, 2015, 9:58 PM


Views: 5942
Re: [jts1957] 17pw26-4
5v there but no 3.3v. my meter is a XL830L i have the red probe in MAX 600V~- 200mA MAX socket, and the black lead in the com port there is another port that says 10ADC but i have never used it, when checking AC i put the dial onto V~ 600, and when checking DC i put the dial onto V-. sorry did not see your bold writing before.


(This post was edited by bubba21 on Aug 15, 2015, 10:09 PM)


jts1957
Veteran


Aug 15, 2015, 10:26 PM


Views: 5938
Re: [bubba21] 17pw26-4
Quote
oo thats weird i put my old board in and got all the voltages +5 on pin 14 3.3v on pin 16
Those two pins are "Standby 3.3v & Standby 5v"

Does your original board use D879 or is it omitted? But if it's omitted then where did the 3.3 you measured come from?


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bubba21
New User

Aug 15, 2015, 11:31 PM


Views: 5936
Re: [jts1957] 17pw26-4
only 5v showing now on pin 14??


jts1957
Veteran


Aug 16, 2015, 1:04 AM


Views: 5933
Re: [bubba21] 17pw26-4
Second try: Does your original board use D879 or is it omitted?

Pin 4: SW_SWITCH = I AM SURE Reads zero when the set is unplugged ... I Need TWO answers: 1) what does it read when set is plugged into mains? & 2) what does it read as/after the power button is pressed, then released ONCE?

Let's see how well you mess this one up before I ask for any others.Angelic


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bubba21
New User

Aug 16, 2015, 6:10 PM


Views: 5850
Re: [jts1957] 17pw26-4
can not find D879 anywhere on the power board, ok here goes be gentle with me. Pin 4: SW_SWITCH = zero when unplugged. Answer 1: When plugged into the mains PIN 4 reads 0. Answer 2 after the power button is pressed then released ONCE i get 15v reading on pin 4.


jts1957
Veteran


Aug 16, 2015, 7:18 PM


Views: 2514
Re: [bubba21] 17pw26-4
On prior: after press gets you 15v. Does it stay or does it go?

Pin 6: ST_BY = I AM SURE Reads zero when the set is unplugged ... I Need TWO answers: 1) what does it read when set is plugged into mains? & 2) what does it read as/after the power button is pressed, then released ONCE? (And does it stay or does it go?)

Also as a side project you may wish to quickly test the parts listed in this kit.
http://www.ohmsupplies.co.uk/...IR-KIT-Q813/Q814-S/C

I assume you've watched: https://www.youtube.com/watch?v=izJnFWLnzR0


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Location: Far, Far Away

(This post was edited by jts1957 on Aug 16, 2015, 7:35 PM)


bubba21
New User

Aug 16, 2015, 7:35 PM


Views: 2508
Re: [jts1957] 17pw26-4
PIN 4 15V stays. answer 1 PIN 6 ST_BY, when plugged into mains reads 00.0. answer 2 when the power button is pressed then released ONCE the reading is 0.00 and stays like this


jts1957
Veteran


Aug 16, 2015, 7:40 PM


Views: 2505
Re: [bubba21] 17pw26-4
Pin 8: BL_ON/OFF = I AM SURE Reads zero when the set is unplugged ... I Need TWO answers: 1) what does it read when set is plugged into mains? & 2) what does it read as/after the power button is pressed, then released ONCE? (And does it stay or does it go?)


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Location: Far, Far Away


bubba21
New User

Aug 16, 2015, 7:48 PM


Views: 2503
Re: [jts1957] 17pw26-4
 Pin 8: BL_ON/OFF zero unplugged. answer 1 reads 0.00 when in mains answer 2 when pressed then released ONCE the reading is 0.00 and stays like this


jts1957
Veteran


Aug 16, 2015, 8:00 PM


Views: 2496
Re: [bubba21] 17pw26-4
Starting to look like it may be Main board.

Did you check my last edits?

Can you confirm pin labels on ODD pins of PL816 from #11 on down.


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bubba21
New User

Aug 16, 2015, 8:20 PM


Views: 2492
Re: [jts1957] 17pw26-4
can not confirm as the board is not marked up, nor is the 28 pin plug, i only have the schematic for the power board, and this is the only way that gives me the information for what number pins are, yes checked your last edits. pin 11 on my schematic says it should be 12v and its reading 0.00


(This post was edited by bubba21 on Aug 16, 2015, 8:26 PM)


bubba21
New User

Aug 16, 2015, 8:37 PM


Views: 2483
Re: [bubba21] 17pw26-4
the main board! is that the power board your talking about or the av board (mother board)


jts1957
Veteran


Aug 16, 2015, 9:41 PM


Views: 2473
Re: [bubba21] 17pw26-4
The schematic is unclear on these. Perhaps you can look at the foils on back of board to confirm? There are TWO 5V's & TWO 12V's.

Pin 11 then must be +12V (NOT +12V_1)????
Pin 13 then must be +33v
Pin 15 IS +3.3VSTBY (there ain't NO +3V)
Pins 17, 19 & 21 then must be +5V (NOT +5VSTBY)????

These Power & Main Right? http://www.shopjimmy.com/toshiba/40bv700b


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Location: Far, Far Away

(This post was edited by jts1957 on Aug 16, 2015, 9:44 PM)


bubba21
New User

Aug 17, 2015, 11:19 PM


Views: 2465
Re: [jts1957] 17pw26-4
have not yet had a look under the board but my schematic says

Pin 11 is +12v
Pin 13 is +33v
Pin 15 is +3.3vVSTBY
Pins 17, 19 & 21 are +5
Pin 26 is +24VA

can not gain access to http://www.shopjimmy.com/toshiba/40bv700b


jts1957
Veteran


Aug 18, 2015, 12:27 AM


Views: 2462
Re: [bubba21] 17pw26-4
Vestel 20519900 (17PW26-4) Power Supply Unit

$68.93
Part number (20519900) can be found on barcode sticker.

____________________________________________________
Vestel 20522664 (17MB35-4) Main Board

$84.95
Part number can be found on the sticker.


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