DJ LED Display is dim?

[djreggiereg]

I have two DMP-555"s for about two years now and today my LED screen has faded to nothing but the upper left hand screen which is very faint. I was wondering if anyone knows if there is a fuse or cable assembly that could be replaced to fix this problem. Am I the first? or is this the begining of all Pioneer LED failures? This really SUCKS!! I can't read S!@*. One thing is that it's like spining on my 1200's without watching the grooves. Someone give a Brotha a hand with this one. Thanks DJ Reggie Reg.

Thank you for this site, I posted this about 4 years ago with no help from the pioneer pro dj website. I have a Pioneer digital music player that turned dim one day after turning it on. I'm a basement DJ that is trying to learn how to repair electonic components. This unit is obsolete and it will cost me cash that I don't have to send it in for repairs. I'm in the process of moving from the East coast to the West of the U.S. and I hope to get this fixed. Also, google djreggiereg and DMP-555 and you will see my post and the other guy that refuses to have an open mind for the "average Joe's that have a special intrest in electonics" but have families to support. I will make copies of my repair manual and take picks later. DJ Reggie Reg

 

[djreggiereg]

DMP-555 wire diagram

Attached is a copy of my wire diagram with most of the pages taken out. If you need a copy give me your email and I'll send the whole thing. I replaced the LED panel "H" with no help, the same exact problem came up. The next step is to replace panel "C". I would like to try and replace whatever resistor or capacitor that is affecting the LED from illuminating.

 

[Nigel Goodwin]

First off, it's NOT an LED display, it's a vacuum flourescent one (VFD).

Dim displays are usually down to heater voltage problems, and you didn't provide enough of the circuit. The heater connections are pins 1 and 2 of socket CN3001, you need to check where they come from - often there will be an electrolytic or two in series with the heater, and these commonly go high ESR (it's a very poor use for an electrolytic).

 

[Menticol]

If you get confused about the ESR thing check this out. Is intended for computers, but the failure is the same

https://www.ehow.com/how_2162895_identify-distended-capacitor-inoperable-computer.html
**broken link removed**

Beware that your faulty capacitors maybe didn't failed with the same spectacularity as the depicted ones, so even if they look good replacing them is better. Follow the wires where the faulty backlight is connected, and then the circuit board traces. There you will find your enemies.

 

[djreggiereg]

Thanks Nigel and Menticol, (VFD) they had another name but this will help me out. I will follw the wires on the pcb when I go to work tonight. I also noticed the pcb diagram has small holes before each item. Can I use my meter to test for an oper or closed circut if I find the correct ground for each or do i have to remove an Item before I test it? Reggie.

 

[Nigel Goodwin]

Thanks Nigel and Menticol, (VFD) they had another name but this will help me out. I will follw the wires on the pcb when I go to work tonight. I also noticed the pcb diagram has small holes before each item. Can I use my meter to test for an oper or closed circut if I find the correct ground for each or do i have to remove an Item before I test it? Reggie.

You need to check the circuit, and see where the heaters are fed from - a meter isn't much use, a scope would be though. But just the circuit will probably be enough, and we can tell you what to change (hopefully).