I will try to give you a general idea how to fool the projector that was designed to squeeze some extra $$ out of your pocket. I will illustrate it with the pictures taken while I was fixing a certain projector but this model is rare and the idea I want to share with you is general. Sorry, it's not a real 'instructable'. I can't name the exact steps for your particular projector but the ideology will remain the same for any case.

Disclaimer - you are going to work with the device that has several dangerous components:
circuit board with live terminals, high-voltage power supply unit, pressurized lamp that can blow up if not handled properly. Think twice and take corresponding precautionary measures to avoid injuries and death :)

P.S. As you can see from the comments in some cases the old lamp may blow up.
I never faced with that myself and the bulb in my friend's projection TV is more
than 10,000 hours old but this "statistics" is not enough so  "forewarned is forearmed".
The safest (and most expensive) way to avoid this problem is ... to buy a new lamp but this
defies the purpose of this very instructable. The compromise is to study the construction
around the lamp and if it looks weak then one can install a metal mesh screen.
The design is up to you - it should have fine openings and at the same time it should
not hinder the cooling.

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robyav6 months ago

sir i have a sony projector vpl-cx76 which i need to convert i have got the led lamp but i am not able to figure out how to fool the projector .i have got the service manual for this projector but i am confused .please help .service manual


ánagy101 year ago

Hi! I have just the same problem with my Benq PE8700. Although I found the service manual in no time (http://www.manualslib.com/manual/249900/Benq-Dlp-Projector-Pe8700.html), unfortunately I was not able to obtain how to bypass the lamp. Could you give me a hand in this?

artemff (author)  ánagy101 year ago
first of all, I don't see the comment you are referring to as to "the same". Can you give more information? Do you want to install another light source or you want to use the old one once again?
In any case, see p.43 of the manual - J1 pin 1 and J1 pin 3 of DMD board - the bypassing starts there.
Lamp hours reset is done through RS232 serial interface - see the commands list on p.60 - lamp reset is a "public function" accoding to p.59.
artemff (author)  artemff1 year ago
OK, then check what's going on with these pins #1 and #3 and try to emulate the signal "original lamp is working" (I understand that pin #3 is responsible for that) when the lamp power supply board is unplugged. When you succeed, just swap the light source.

I'm sorry, you are right. I would like to change the lamp to a LED source

repa321 year ago

Hi, I need help as well. I have got an Acer P1220 projector. I reached the lamp changing time but did not care to much when I had a problem and switched off all fuse in the house finally when I could switch on my projector there was a big sound and went off my projector. Probably it is the lamp, that's why I checked the lamp type I mean the cheap solution to buy only a lamp with the same parameters. When I received it I recognised the wire which goes to the lamp is broken as well. So I went to the electrical company who put a cellotape on it. I tried to pu everything together how I found earlier and switch on. Fans start but the lamp is not and after a couple seconds the lamp warning light start to flash and switches off itself. If you can give me any idea to fix it it would be fantastic.


artemff (author)  repa321 year ago
you can upload the picture to any of the free image hosting sites like picasa and provide a link. Another option is to use "add images" button - in my account, I see it just under the "reply" window on the left.
repa32 artemff1 year ago
My email zoltanrepasi37@gmail.com then I can send pictures.
repa32 artemff1 year ago
Hi, I hope that will work. I had this picasa before but did not care about it. Here are the pics. https://plus.google.com/app/basic/photos/photo/106994802370728900426/6020979661870170418?cbp=ro8gslviving&sview=20&cid=5&soc-app=115&soc-platform=1&pct=ab&pcv=6020975390179729217&spath=%2Fapp%2Fbasic%2Fphotos%2F106994802370728900426%2Falbum%2F6020975390179729217&sparm=cbp%3D3z0007leuzxq%26sview%3D26%26cid%3D5%26soc-app%3D115%26soc-platform%3D1%26spath%3D%2Fapp%2Fbasic%2F106994802370728900426%2Fphotos%26sparm%3Dcbp%253D3z0007leuzxq%2526sview%253D26%2526cid%253D5%2526soc-app%253D115%2526soc-platform%253D1%2526pgpnum%253D1%2526spath%253D%2Fapp%2Fbasic%2Fstream%2526sparm%253Dcbp%25253D1b4txjy6qw8ge%252526sview%25253D26%252526cid%25253D5%252526soc-app%25253D115%252526soc-platform%25253D1 and the other https://plus.google.com/app/basic/photos/photo/106994802370728900426/6020979935003841842?cbp=1mghre714ucig&sview=20&cid=5&soc-app=115&soc-platform=1&pct=ab&pcv=6020975390179729217&spath=%2Fapp%2Fbasic%2Fphotos%2F106994802370728900426%2Falbum%2F6020975390179729217&sparm=cbp%3D3z0007leuzxq%26sview%3D26%26cid%3D5%26soc-app%3D115%26soc-platform%3D1%26spath%3D%2Fapp%2Fbasic%2F106994802370728900426%2Fphotos%26sparm%3Dcbp%253D3z0007leuzxq%2526sview%253D26%2526cid%253D5%2526soc-app%253D115%2526soc-platform%253D1%2526pgpnum%253D1%2526spath%253D%2Fapp%2Fbasic%2Fstream%2526sparm%253Dcbp%25253D1b4txjy6qw8ge%252526sview%25253D26%252526cid%25253D5%252526soc-app%25253D115%252526soc-platform%25253D1
artemff (author)  repa321 year ago
I get "Error 400, file not found" when I try to open the links. Can you upload them using "add images" button?
repa32 artemff1 year ago
Im not sure where is that add image button, under the reply I dont have anything.
artemff (author)  repa321 year ago
From this story, I can't establish a link between the lamp hours counter and blowing of the fuses in your house. Can you provide a picture of the lamp and of the "fixed" wire? If it's a hi-voltage wire, a simple patch might not work (in fact, it can be also dangerous since nobody knows where the discharge will happen).
repa32 artemff1 year ago
How can I attach picture? When I put back the fixed wire with the old lamp it started to give burned smell. I switched off straight away. Then I changed the lamp. There was no smell. Worked all fan but no picture and after a couple seconds the lamp light start to flash and switch off. There was a white powder around the lamp after the blast sound.
zopo1 year ago

Hi, I need help with my kodak dp 2000. Here is a photo of boards, i will post more detail photos. http://s22.postimg.org/5v7anikqn/kodak_dp2000.png Thanks

artemff (author)  zopo1 year ago

first of all - do you try to fool the lamp hours counter or to replace a lamp with a LED? Is the projector still working or the lamp doesn't start (in the former case, one can measure the voltages on the logical connector).

Looking at the photos I would say that the high-voltage power supply shares the board with the "normal" power supply, right?

Try to find the circuit diagram for this projector - it will also help.

zopo artemff1 year ago

Thanks for fast reply, i figured it out but right now i'm trying to find some good lens for led but i'm completely lost, can you help me with choosing lens ? I have 20w led, it is about 5x5cm. Thanks :)

zopo zopo1 year ago

Can i use "bi-convex lens" ?

This looks perfect but I'm not shure.


artemff (author)  zopo1 year ago

The only limitation I see is geometrical factor - how much space do you have to install the LED + lens system? I would say that you need at least 68 (focal length)+20 (lens thickness)+20 (LED+radiator)=~110mm.
You can also check this link on LED mods: http://hackaday.com/2013/03/28/epson-projector-led...

zopo artemff1 year ago





Can you sugests me some lens ? :) Thanks.

artemff (author)  zopo1 year ago

hmm, that's a good question - I never tried to make a collimated beam from a source of this size. I would try a telescope-like two lens system, but you don't have enough space for it. In principle, the lens you found might work. I saw schemes with extra reflectors on the sides to return the escaping light back to the system. I would also think about adding a fan to the LED.

zopo artemff1 year ago

Heatstick with fan is on to do list but for first i have to make collimated beam if it is even possible from this led. Btw I'm not limited with space, i can a nev case for projector.

artemff (author)  zopo1 year ago

then I would say that a system of "pre-collimator"+lens+lens will make it close to telescope (go from right to left in this sketch http://www.studydoctor.co.uk/site/wp-content/uploa...)

In any case, you'll need the lens you were going to buy so you can start with it. If the light losses will be too high (only part of LED light will forma a collimated beam) then you can add a second lens and some pre-collimating reflector in front of the first lens.

zopo artemff1 year ago

Thanks for pdf. I just ordered http://pages.ebay.com/link/?nav=item.view&id=171199870428 for start digging dhis optical sh*. :D

artemff (author)  zopo1 year ago

the link doesn't open but, anyway, good luck :)

zopo artemff1 year ago

Ou, damn. Here:


aduy1 year ago
hello, ive got my projector all apart and found the three optocouplers, but the signal doesnt change when I turn the unit on and off even though the lamp light blinks on and off.
artemff (author)  aduy1 year ago
Hello, can you provide more information? Do you mean that the lamp power supply is connected with the main board through optocouplers? I wonder what is the purpose of three optocouplers, one should be enough. Perhaps, the system is sophisticated and the power board sends a digital sequence to tell that everything is OK, but it's an overkill.

Just to be on a safe side - what kind of the problem you are dealing with? A projector with a "native" lamp which is over NNN hours on it and which was working before?
aduy artemff1 year ago
ok so im basically just trying to disable the lamp and trick the main board into thinking the lamp is fine. i have an led light source that im going to replace the lamp with. it is a dlp projector, an optoma ep771 to be exact. i saw a video and it explained that almost all projectors use 3 optocouplers, two of them go from the main board to the lamp supply, one comes back, it seems as if the one that comes back is sending a digital signal of some sorts, instead of a simple on/off it must be sending a code. perhaps ill take it into the local hackerspace and hook it up to the scope and see if i cant decrypt the code.
artemff (author)  aduy1 year ago
another option would be to find the IC which decrypts the signal from the optocoupler and hope that it provides 1/0 on its output.
However, all this seems to be overcomplicated - I wonder why did they choose this approach. BTW, could you add a link to the video you mention?
Back to your problem - do I understand correctly that the projector works, but you want to change the light source? If this is really the case, you can check all the signals with the scope and then try to emulate them. It might require adding something like Arduino, but it should be doable.
aduy artemff1 year ago
I wonder if there is a way to trick the ballast into thinking it is powering the bulb.
artemff (author)  aduy1 year ago
this _might_ be possible (the lamp and the ballast have different voltage/current characteristics, especially during the ignition cycle), but this would kind of defy the purpose - you wanted to use a different light source and here there will be two parallel systems, one of which will be just producing heat.
I would still try digging in the direction of making the main board believe that the lamp is present through simulating the logical signals.
(of course, it would be much easier if the projector could be assembled back to working condition)
artemff (author)  artemff1 year ago
I guess you saw the diagram on p.15 of the service manual - indeed, the lamp module talks to a mainboard (RxTx to DDP2000 module), so it becomes tricky and your solution might be not so bad - otherwise you'll have to emulate all the signals somehow.
dtommyd2 years ago
It looks like folks are still looking at this thread so I'll add a question. Hopefully someone can help me. Instead of photos I actually found the service manual for it. Look for the "Get Manual" link under the preview photo on the download page.

I have pretty much the same question as everyone else. What do I need to jump to fool it? It's for the cp-s210. The photos are a few screenshots of the pdf I linked to. I plan on powering the lamp separately. I just need the projector to power up. I'm also aware of the lamp door switch I'll need to engage.
artemff (author)  dtommyd2 years ago
check page 23 of the manual - it just says "reset the lamp timer". I do not see anything else on the diagram, which would prevent one from doing it for an old lamp, there are no control circuits.

If the projector just doesn't work, then it's a separate problem and the manual contains a lot of useful information regarding troubleshooting.
dtommyd artemff2 years ago
The original ballast and bulb are out of it. The bulb blew. When I go to start it up the blue startup screen doesn't come on. (I am shining a pretty bright 4 watt led bulb powered from 12v outside of the projector.) The main power led blinks green for about a minute (searching for the bulb?) After about a minute the power led blinks red and the bulb led goes to a steady red. It then shuts itself down after about a minute and both the power and bulb leds stay steady red.
Are you saying that if I put any 130 watt UHB or 130 watt bulb in there, it will work? Or are you saying that with the ballast and bulb out, it should be working? Theres no blue startup screen and of course there is no menu. I've done this before with another projector and I'm aware of the dimness and I'm sure I'm out of focus but I was moving that around during startup and see no blue whatsoever.
artemff (author)  dtommyd2 years ago
Do I understand correctly that you try to power it on without any bulb at all?
Then it is not surprising that the power board reports a failure. The question is - do you want to use an alternative bulb and want to fool a projector?

If you really plan to do it then you have to change pin 3 (E804) from "Lamp missing" to "Lamp present" logical level or to remove the power board completely and just put "Lamp present" voltage (check the manual - I don't know the logical level voltages in this projector) to this pin.
artemff (author) 2 years ago
most probably, this is a loose connector or a failure of "blue" LCD chip (this projector uses 3 separate LCDs) or of its driving board. Sorry, I don't know where to get the parts and I suspect that they will be more expensive than a used projector (especially, with a non-working lamp).

I would carefully open the projector, identify the LCD and its connector and slightly move the latter - if the line disappears, then the problem is half-solved (proper restoration of the contact might be quite tricky).

P.S. Usually, there is a safety switch preventing operation with a cover removed.
P.P.S. Be careful if you want to bypass this switch and play with a powered projector - first of all, there's high voltage. Second - it's pretty easy to shorten something or break/misalign LCDs.
kahodges2 years ago
I was wondering if you could help me? I have a used Hitachi CP-X1250 projector that shows a blue vertical line on the left side of the screen, from top to bottom. Which part could cause this, and do you have any idea where I can get parts for this machine? Thanks in advance.
hassan24952 years ago
Hi, thank you for the reply. This is the board attached to the power board which carries the optocoupler circuit. The white on is the signal wire.
there is a good chance it is not just a logic level but there is serial communication between the main-board and the (ballast) high voltage power supply since is a newer projector that can be the case also the proximity to that Nec microcontroller uPD78F0511 can indicate that but I'm not sure.
With a replaced lamp it runs fine. so the rest of the parts are predicted to be ok. Can you help me tricking the lamp ?
artemff (author)  hassan24952 years ago
OK, if it's a real communication between the PSU and the main board, then it's a different story - we don't know the protocol and we don't have hardware to emulate the "OK" signal.
The first idea, which comes to mind is to measure voltage and current for the working lamp and for the faulty one (better with oscilloscope since the ingnition phase might be the cause). The problem is that everything is insulated + you need to solder 1:10-1:100 voltage divider to measure the voltage with a regulat voltmeter and you need to break the circuit with an amperemeter to measure the current - not a good idea.

Another option would be to compare the voltages on all the 'thin' wires, which connect PSU with the main board, for a working lamp and for a bad one. Again, little can be done if the PSU is talking to the mainboard and diagnoses some problems with the lamp.

BTW, how does the lamp look like? Is it just the lamp or something is mounted on it?
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