Rca L32hd32d

[Kevin O'Henly]

Good folks at Badcaps,

symptoms:
~ TV power-on dual-color LED shows green after red.
~ backlighting winks on and off once an stays off.
~ no bulging capa or bad caps using the ESR scope and signal generator method.
~ no sound from external signal sources or internal DVD.
~ DVD responds to panel switches: "ON" and "EJECT"

RCA has not provided the power supply connector voltages for CP3908-1 and CP3909-1. These connectors go to the control board.

Thank you for any assistance you can provide.

[Wizard]

Re: Rca L32hd32d

This is horrible version of "T-CON"-less design. If there's problem with display and is traced to the this, whole mainboard replacement is necessary.

Make sure there's none SMD fuse blown. Also make sure the backlight is perfectly neutral not pink or missing tube lit or 2 second and out syptom. This bear investigated especially around lamp supply & lamps section.

Cheers, Wizard

[markchess1960]

Re: Rca L32hd32d

I may be of help with this.
I have repaired this problem several times. For me so far the repair has been:
On the main board (the one in the photo with the tuner and ribbon cables that go to the lcd panel itself) there is a surface mount ic. It is a 6 pin op amp - location IC1303. It usually shows signs of overheating and sometimes one or more of the traces connecting to it are burnt. The part number for it is: ec5461ab3-g and you can find them at B&D Enterprises online.
You need some pretty good soldering skills to replace it though... it's very small, has to be installed in the correct direction, and you may have to repair or jump burnt or broken traces.
You can find the location of this part by looking at the board about an inch inboard of the left edge of the left (as viewed from your photo) lcd panel ribbon cable connector CP1203

[Mrtello]

Re: Rca L32hd32d

My Problem with this tv ( L32hd32d)is that i got power but no picture the backlight is on but no display or menus, i got no voltage on the board that is on top of the lcd panel

[bobsovacool]

Re: Rca L32hd32d

I may be of help with this.
I have repaired this problem several times. For me so far the repair has been:
On the main board (the one in the photo with the tuner and ribbon cables that go to the lcd panel itself) there is a surface mount ic. It is a 6 pin op amp - location IC1303. It usually shows signs of overheating and sometimes one or more of the traces connecting to it are burnt. The part number for it is: ec5461ab3-g and you can find them at B&D Enterprises online.
You need some pretty good soldering skills to replace it though... it's very small, has to be installed in the correct direction, and you may have to repair or jump burnt or broken traces.
You can find the location of this part by looking at the board about an inch inboard of the left edge of the left (as viewed from your photo) lcd panel ribbon cable connector CP1203

Mark- thanks for sharing this fix... it looks like my RCA had this problem, and yes, the IC was hard to R&R (i even trashed a new one by not using a small enough soldering iron tip and magnifier). What i did was surf around for a less expensive suitable cross referenced IC. The National Semi LM7321/7322 has specs that are close enough. I picked the 8-pin soic package, which will run cooler than the original IC (5-pin sot-23), since it is larger (and should therefore last longer reliability-wise). I bought an 8-soic experimenting circuit board (PCB) to solder this 8-SOIC onto. Then i soldered small leads to the TV pcb (very small leads such as those used for wire wrapping). Individual leads from stranded wire can be used, with thin shrink- tube used to insulate them. You can download the datasheets (original EC5461A) and replacement Nat Semi LM7321/7322 from their websites, cross reference which pins to solder where via the datasheets, and enjoy your tv again! By the way, the amplifier IC is used in the unity gain mode, which means that 2 of the pins are connected together (output connected back to inverting input) which can be done on the experimenting pcb, rather than on the main tv pcb (much easier to do). A total of 4 small wires are required to connect this IC pcb to the main pcb (power, ground, output, and non-inverting input). You can verify this by looking at the main pcb and the EC5461A datasheet) This fix cost just $5 rather than $20 plus! Again- i would not have accomplished this without Mr Mark Chess's input, so thank you Mark Chess!

[Plocmstart]

Re: Rca L32hd32d

I may be of help with this.
I have repaired this problem several times. For me so far the repair has been:
On the main board (the one in the photo with the tuner and ribbon cables that go to the lcd panel itself) there is a surface mount ic. It is a 6 pin op amp - location IC1303. It usually shows signs of overheating and sometimes one or more of the traces connecting to it are burnt. The part number for it is: ec5461ab3-g and you can find them at B&D Enterprises online.
You need some pretty good soldering skills to replace it though... it's very small, has to be installed in the correct direction, and you may have to repair or jump burnt or broken traces.
You can find the location of this part by looking at the board about an inch inboard of the left edge of the left (as viewed from your photo) lcd panel ribbon cable connector CP1203

Thanks for the tip. I also found that the voltage at the inductor L3502 powers up to 3.3V and then drops to around 900mV as the op amp must pull the supply down. I removed the op amp at first to see if this would keep the rail from dropping and it did. So I connected all the cables and the screen works fine again with no part populated. So I'm wondering what this part is doing. Does it set a bias voltage on the LCD panel, or some auxillary function for the TCON? I will probably still get a replacement part, but just curious how critical it might be. Thanks.

[A Man]

Re: Rca L32hd32d

I just bought one of these sets and found the mains 6.3A fuse and varistor were toast. I replaced both and now get a red LED when I plug in the set. The LED changes to green when I push the power button and the DVD will load/eject. The display momentarily flashes "Please Wait" while the backlights flash on, then they go off and it stays like that.

I've checked IC1303; it appears intact and normal. So I don't believe that is my problem.

I'm leaning towards this... but need a little guidance please.

This is horrible version of "T-CON"-less design. If there's problem with display and is traced to the this, whole mainboard replacement is necessary.

Make sure there's none SMD fuse blown. Also make sure the backlight is perfectly neutral not pink or missing tube lit or 2 second and out syptom. This bear investigated especially around lamp supply & lamps section.

Cheers, Wizard

Thank you!

[A Man]

Re: Rca L32hd32d

Does anyone have the service manual or schematic diagram for this set? I've been unable to source one on the internet.

Particularly I need to know the value of D3802. It is on the input side of the power supply and tests open in both directions.

Any help would be greatly appreciated.

[tom66]

Re: Rca L32hd32d

That is likely a TVS, and unlikely to be at fault. It will normally test open.

[A Man]

Re: Rca L32hd32d

That is likely a TVS, and unlikely to be at fault. It will normally test open.

Could this Transient Voltage Suppressor possibly fail if the mains fuse and varistor were both blown?

If this is not the problem, any ideas where to look? I have power to run the audio and DVD drive but the backlights shut off after saying Please Wait. This is my first problem like this.

[tom66]

Re: Rca L32hd32d

Oh, if the mains fuse is blown, that could be the fault. However, if it is open, it has not yet failed.

[A Man]

Re: Rca L32hd32d

Oh, if the mains fuse is blown, that could be the fault. However, if it is open, it has not yet failed.

I've already replaced the mains fuse. (See post #7)

Are you saying the TVS will show show shorted if it has failed?

[tom66]

Re: Rca L32hd32d

Yes, almost always, unless a surge was really bad and completely destroyed it, but that usually shows externally.

[techtip]

Re: Rca L32hd32d

32hd32d power supply

[techtip]

Re: Rca L32hd32d

l32hd32d timing controllr2 schematic

[mrdoob]

Re: Rca L32hd32d

Anyone have the regulator section of the schematics for this TV. I changed the op amp a couple of years ago and now I have the same issue where sound but no picture (back-light on). But there is no VCC getting to the op amp. I even disconnected the VCC from the op amp to make sure that the voltage wasn't being pulled down.
Thanks.