Dead Laseractive PAC?

[SPAZ-12]

Sigh. I really hope this isn't broken.

I got my Laseractive in the mail yesterday, with the sega PAC-S10 and controller. The guy who sent it packaged it up real nice, in a huge box full of packaging peanuts. The system worked fine right out of the box, it plays LD's and CD's just fine, and the PAC-S10 worked just fine.

So tonight I was getting some actual playtime on the thing, and cruisin' through Sonic 2. Things were just fine, and I was enjoying the nice audio that this system puts out, but then just as I beat Hill Zone Act 1, the screen went black. At first I though that I had just witnessed my game die, so I popped in another game, and it too didn't work. After trying a couple more games I had to admit that the PAC was the problem.

If the PAC is not plugged into the Laseractive then the player still plays CD's and LD's just fine, audio and video are both working. But, if I have the PAC plugged into the system then all that I get is a green screen which then fades to black.

Normally with the PAC installed and no game inserted I should see a nice splash screen with some logos on it and instructions, but this has been replaced by that green screen. What seems to be happening is that the PAC now thinks that there is always a game installed or something, since while it was still working it would display that green screen for a second before booting into "Genesis mode."

Does anyone have any idea of what could be wrong? I know the Laseractive is known for PSU issues, but I think that is ruled out since the player still turns on. Please help, this is my most expensive video game system, I don't want to lose it after only one day of playing it...

I haven't checked the inside of the unit yet, I have to find some security bits for that. maybe I'll find a loose wire or something.

[SPAZ-12]

"Update"

Well, I opened it up. Since the security screws aren't recessed I could just use pliers to take them out, always nice.



I really don't know what I might possibly be looking for though. I don't think that I am looking for a failed solder joint since the problem happened during gameplay, and is persistent.



One thing to note is the EPROM chip in the front left, the large socketed chip with the white sticker on it. I assume that this is some sort of BIOS chip, which actually might explain the lack of a splash screen if it suddenly stopped working, though I don't think that it would have caused my game to crash. My PAC was made in 1993, so I guess this is a possibility though.

The white sticker is over the window on the chip, and says PIONEER PDJ008D. The chip itself is a Texas Instruments chip, 27C210A-15, LUP9245189. I know that EPROM's are supposed to degrade over a length of about 15 years, I really hope this isn't the problem though, because I'm not outfitted to burn EPROM's, plus I don't know where I could find a replacement BIOS anyhow. I have found Laseractive BIOS-es, but none for the PAC itself.



The only thing that I could potentially see as causing a problem like mine is the rechargeable battery. What is this even for? The Genesis didn't save data internally or anything, but what it it burnt out suddenly? I don't know.



This is something that I found odd, this almost looks like a modchip or something, although I'm about 99% sure that it was installed in the factory. Darn weird though, I guess they found some mistakes in the board after they started production or something.

I hope that these pictures help, or that someone at least finds them interesting. Any ideas about what to check for now?

I was thinking about pulling out the battery or the BIOS and seeing if that did anything when I attempt to power the system on. Could this cause further damage?

[FABombjoy]

The BIOS and battery are for Sega CD, and presumably Laseractive functions. Try running it with that upper board removed. I had a Sega PAC once that did the same thing as yours and worked without that board installed. Not that this is a fix, but if it works without it, could help lead to discovering the problem.

[SPAZ-12]

I think you're on to something there Bombjoy.

I removed the upper board and plugged the PAC back into the Laseractive. When I did that the flash screen came back, so the PAC appeared to be functioning normally. Then I put in Batman & Robin to see if Genesis games would work. It was really finicky, and I had to insert and remove the game about 20 times to get it to run without graphical glitches, but the game worked. The only thing missing is sound.

So presumably that board handles the audio for the Genesis. Later today I'm going to go buy a Sega CD game to see if that works, because that board might also have some important role for the Sega CD.

I'm not sure what could have failed on that upper board, but I think that the "modchip" is my prime suspect right now. I'm going to test its components and its connections to the upper board, hopefully the problem is a simple as that.

[SPAZ-12]

I've now tested the PAC with a Sega CD game--Sewer Shark--and learnt nothing new. The Sega CD game acts exactly the same as a cartridge game as far as the PAC is concerned; I can play the game, but only with the upper board removed, so no sound.

So now I know that the upper board is in charge of sound for game playing. But I'm not sure if the problem lies there or not. Sometimes even without the upper board plugged in I still get the green screen of death. It doesn't mean that the problem is not on the upper board, but it raises some doubt.

I have now also tried to run the PAC with that EPROM chip removed. If I inserted a cartridge then the system would boot the game and work like a normal Genesis; if I tried to turn it on without a cartridge then all that I would get is a black screen. So, Bombjoy, it appears that you are correct about it being the bios for the Sega CD and other Laserdisc functions. I think that it is fairly safe to rule it out as a problem now.

If only there was more information about the Laseractive PAC's on the web, but I have almost nothing to go on right now.

[FABombjoy]

Pioneer usually has great service manuals, but I'm not sure if they ever came out one for the PAC modules, which could be helpful here. I ended up selling mine before I had a chance pinpoint the problem, but yours is doing exactly the same thing mine was doing. So it's either the same physical unit that I had, or there is a common failure mode. I got nothin' offhand, save to wish you luck