*Modified to show problem, probable cause and repair.
This particular series of 9th generation Kuro plasma t'v's has a seperate media receiver which is connected to the panel by Displayport. The panel has to be connected to the media receiver to work. If there is a problem, the LED of the media receiver will blink.
Problem: Set will not turn on or only sporadically, blue LED blinking eight times in a row
Probable cause: One of the voltage regulators is faulty (part is NJM2846DL3-18) These cost a couple of euro's or dollars, depending where you get it. I got mine in Germany from
http://etus-landgraf.com/index.php/component/virtuemart//pioneer/tv-plasma/krp-500a?oberkategorie=3&hilfskategorie=12&unterkategorie=2231Location: These voltage regulators are on the underside of the mainboard of the media receiver. There are several. Most likely culprit is ic 4606, but please measure during startup phase to be sure.
Difficulty: Board level repair on a small part. Not quite SMD, but very easy to lift solder pads. Be sure to know what you're doing and have proper desoldering and soldering tools and skills.
Otherwise, please leave the repair itself to a professional. The TV is worth it (best plasma ever made). Seperate media boxes are hard to come by and fetch quite a lot on Ebay.
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Original post:
I picked up this set with a defect. Fault is as follows:
When power is applied, the set will either stay in standby (red LED on) or give a fault. Most often, when cold the set will not give the fault and switch on. It can then be used for as long as I like with all possible sources. When I switch off and on again, it will show the fault and fail to switch on.
I have the service manual for the panel and the media receiver including block diagrams and such.
This fault is flashing of the blue LED on the Media Receiver eight times in a row. This is a shutdown mode, based on failure of the IIC communications. There are several faults possible.
When pressing the info button on the remote during the shutdown, the fault is further designated by the orange LED. It flashes one time. This indicates a fault in communication with the DVB-T tuner frontend.
For all IIC communications faults, the main IC that controls the periphial IC's on the pcb is a Pioneer/NEC unit. It is mounted as a BGA package.
Anyone with experience with these units? As Pioneer has ceased plasma production years ago, spare media receivers are hard to come by and hideously expensive. I would be inclined to try a board/component level repair. Not having measured properly yet on the board, my current working hypotheses are:
1. BGA solder failure on the main chip, rework/reball needed.
2. Auxillary componentry such as onboard voltage regulator failure. Need to measure/probe signals with a scope or sniff out I2C communications.
I don't think it's a fault in the panel as then the panel LED would blink to indicate a fault there. All indications show a fault in IIC communications line with the tv-tuner module. This fault does not occur in a cold situation.
I can share the service manuals if anyone wants to take a look and chime in.