ForCustomerHi Louie I have another Pioneer CDJ2000 which doesnt power up. So i checked the fuses we checked for the last one and they checked out ok. So I proceed to open it up and remove the metal cover which covers the power supply assembly. Once removed I power up the unit to take voltage measurements and the unit powers up fine and functions fine. So I put the metal cover back on with all the screws and it doesnt power up. So I remove a few screws and turn it on and it powers up and works fine. I attempt to put the remaining screws back on and once I touch the screw to the metal cover one of the led briefly powers on and off (just the led with the power cord unplugged). After I screws the remaining screws the unit doesnt power on. I removed the 3 screws on the left hand side and it powers up fine. What could it be?
Also I noticed that there is a transistor on the left hand side screwed on the metal chassis which the cover screws on to so maybe when I screw the metal cover to left side where the transistor is screwed to its grounding out maybe?
I'm attaching 2 pictures one with the metal cover and the other which is the power supply.
I screwed all the screws back without the metal cover and it power up fine.
The 2 screws in question are the ones the screw to the bracket that the resistor is screwed to. If I screw them both in all the way it doesnt work. If I unscrew them half way with the power plug unplugged I see the led briefly come on and off and than I turn on and its fine. So now the screws are half way in but when I screw them in all the way it doesnt work.
Where is this washer located? I dont see it.
I don't see any washers Louie. Are you seeing this in the service manual? If so what page? I took out the power supply and dont see any washers. The bracket on the left is held with one screw from the bottom of the board and another screw which goes from the transistor to the bracket. These two screws have washers but they are metal.
So I screwed the screw by the cn2 connector all the way in and it didnt work. I unplugged the power plug and proceeded to unscrew it a little and I saw the led light come on for a second. Now with the screw half way screwed in the unit works fine. Weird. What does the led coming on for a second indicate?
Its point .1 ohms both ways
So I resoldered RC101 and now it doesnt turn on at all. How do I check RC101?
RC101 are 2 diodes in parallel. It could be tested using an ohmmeter where it would show continuity in 1 direction but high Ω when the test prods are reversed.
Do I have to remove it from circuit or can I test in? Which pins are which?
Im sorry but can you please explain the pin outs. Looking from the top if I have the board side which has the plug towards be and rc101 on the other end which pin is 3? Also can please explain which pins to test. If you think I need to desolder to test I will.
Ok so I desoldered it and understand the pins. If Im looking at the chip from the front pin 1 is to my left and pin 3 is to my right. Please tell me which pins to test.
pins 2 and 3 gives 8.36Kohms. Sorry for the dummy questions. I appreciate your patience as Im a total newbie to the world of electronics.
I have the black probe to pin 2 and red probe to pin 3 most of the time I get around 8.36K ohms but on some occasions I get 33.4K. Red probe to pin2 black probe to pin3 I get keep gettting OL pulsing on the screen.
8.36KΩ more so 33.4KΩ are too high readings. would expect the forward reading to be around 500Ω only. The OL on reverse test is good.Are you using the lowest range on the continuity function of the meter?
Those readings are ohms readings. Do you want me to test in diode mode? In diode mode black probe to pin 2 red to pin 3 I get .200 reversed I get OL.
Pin 3 trace of rc101 to pin 1 & 2 of cn2 I get continuity on both pins. Pin 2 on rc101 to pin 1 & 2 on cn2 I get one beep on both pins and it stops.
What does the 1 beep mean?
Ok give me a few minutes. Also what does the 1 beep mean and it stops.
Ok so I soldered rc101 back no I get no power at all. I did the same continuity test and get the same results.
F1, TH1 & TH2 have good continuity
I get 162vdc on c5
And is there +12 on pins 4, 5 & 6 of CN2 with either pin 1 or pin2 as reference ground COLD side?
pins 4 & 5 are .794vdc pin 6 is 12.21vdc
That would mean that there is standby +12 hence the power supply is functional and is waiting for a turn on signal on pin 3 of CN2. Once this signal is received, then it would turn on the other +12s on pins 4 & 5.It would appear that there is no signal to turn on on pin 3 or if there is, then auto-protect mode is kicking in.Or R110 may have opened.
R110 is a resistor correct? I looking at it on the top of the board and it doesnt look like a resistor just a thin piece of metal with 2 legs? How can we test this?
Louie if you look at the pic at r110 there is no resistor just a thin metal
jumper bar reads 0ohms
during standby by start at .456vdc and decreases
attempting to turn on .156vdc
pin 1 & 2 is .1ohms pin 1 & 3 starts at 10.5k and climbs
pin 3 11.15vdc
pin 4 & pin 5 start at .045 and decreasure
pin 6 12.21vdc
Johnny, the fault seems to be elsewhere. It would appear that there is nothing wrong with the power supply board.Follow the wires from CN2 to CN7302 of the A board. Check continuity of fuses P7001 & P7003.
P7001 & P7003 check out ok
I was just messing around and pushed the transformer down on the secondary side next to rc101 and it powers on.
CN2 connector is getting hot and I smell something burning.
Remove the connector to CN2, unplug unit.
Were the T1 transformer pins also re-soldered?
No i didnt resolder the t1 yet
Louie I pushed the transformer down it powered up but not a %100 and I started to see light smoke and smelled something burning. I kept it on and used my temperature gun and found L101 & L102 reached 200 degrees fahrenheit.
pin 1 as ground
pin 2 reads .1ohms
pin 3 reads OL
pin 4 reads .745 and decreases
pin 5 reads 1.549mohms and decreases
pin 6 reads 1.274mohms and increases
Louie just an observation. When I press down on t1 everything works fine including the screen and l101 l102 dont get hot. I will measure resistance now
I already resoldered t1 pins 1-6 already but it still wont turn on unless I push down on t1.
I try and pin 3 of rc101 to pin 1 of t1 and get nothing. I try pin 2 of rc101 to pin 6 of cn2 and get continuity
pin 3 of RC101 to pin 1 of CN2 is good continuity
Louie by pushing t1 down im not touching any of the windings inside am I? Do you think t1 is bad?
Louie r114 the pad right next to it appears to be from t1. I desoldered it and I dont see the leg from t1 I just covered it with solder for now. Do you think thats the culprit? I used a desoldering pump and maybe it sucked it in.
Now when I push t1 down it wont even turn on
Louie. I desoldered t1 and got a leg from another component and soldered it to the broken leg on t1 and it works fine now.
So how about the smoke that was be produced. Will it have any ramifications?
Also, the pin before r114 is on the primary side? The pins on the other side from 1-6 are on the secondary side?
Why do you think L101 & L102 smoked and got real hot when the pin was broken and making intermittent connection? Just trying to understand what happened so I can learn from it.
I guess ignorance is bliss. If I knew any better I probably wouldn't have done it. Hehe. I figured I had nothing to lose. If it didnt work I'd order a new power supply.
I will study your explanation along with the service manual.
I just want to make sure I understand how T1 is wired on both sides.
On the primary side the only pins relevant are 4 & 6 which get the 120 volts and on the secondary side pin a is connected to pins 4 & 5 of cn2, pin b is connected to pins 1 & 2 on cn2 and pin c is connected to pin 3 on cn2. Am I correct?
I should be able to read 120 volts AC at pins 4&6 on the primary and 12 volts DC on pin A & C on the secondary. Am I correct?
I also notice that pin B on the secondary side is connected to ground which is tied to pin 1 on cn2 and cn1. Am I correct?
Also if the fuse keeps blowing what would the culprit generally be?
12 volts DC on pin A & C on the secondary - no, the +12 would be after their diodes RC101 and D101 respectively;
So where would I position the probes to get reading for the above?
fuse keeps blowing - if immediately upon plugging in, then likely a shorted NR1.
Generally speaking if a fuse keeps blowing up what compenets would be the first suspects?
In any smps generally speaking if a fuse keeps blowing up what components would be the first suspects?
By order of likelihood on any SMPS:
So a varistor & thermistor should be measured for resistance. If it is a very low value that means its good. If its a very high value or OL that means its open? Once these components are open they send alot of voltage to the circuit and the fuse blows? Is that correct?
Not exactly that way on both...On a varistor, the resistance should be high. If it is low, that means it is failed and therefore the fuse would blow.On a thermistor, the resistance should be low. If it is high, that means it has failed and the circuit would not receive voltage through it. Still, a faulty thermistor would not be able to blow a fuse.
Ok so right after the main fuse is always a varistor? Kinda hard to tell them apart.
Almost always, yes and both looks like a disc capacitor.
Good evening. Hope your doing well with the typhoon and all.
I'm glad to hear you and your family are ok. I was worried. I'm watching CNN here in NY and the videos and pictures are unreal. They said the wind speed reached 200 plus mph. So far 1200 confirmed deaths.
I hope you have clean water and food readily available?