I was wondering how the light show is supposed to behave. My GI stays on the entire time and I was wondering if this is normal. The GI does shut off during tests. It just seems like when the intro starts and the explosion sounds are going on with the flashers activating that the GI should either be off, or turning on and off in different sections. Is this a missed programming opportunity? Or is there something going on with my machine?

I have all LEDs in my machine and I turned dimming to off in the menu. Actually, that brings me to another question, why is there a dimming option?

Thanks!

Am I suffering from ghosting? Or is that one an issue with the insert lights?

Bump because I don't have access to a second machine.

Demolition Time is tough to reach I guess.

Thank you for letting me know. I thought something was off. I will have to relamp all if my GI back to normal incandescents and see if it is simply because I have LEDs, or if I have an issue. I didn't want to spend the time on that until I knew there was actually a problem.

But, shouldn't the LEDs at least shut off? Hmmmm.

Is there an add-on controller that can dim the LEDs or turn them off at the appropriate times?

I agree with this wholeheartedly. I don't want to lose the effects so unless I can get an add-on device to let the LEDs do them, I will be switching back to the incandescents.

Do the backbox lights also turn off? Thank you.

I play with all the lights in the room turned off. My Sorcerer looks really cool when the lights shut off and the eyes on the back of the playfield are lit before multiball starts. That's why I'd like to have my GI on DM do what it is supposed to. I want the intended presentation. But, I'd also like to still have the LEDs because I like the way DM looks with them. Guess I'll just have to decide what's more important.

Damn. I got excited for a minute. I saw that there is an LED OCD board, but that only affects the controlled lamps, not the GI. However, that may still be something I add in the future, it won't help me with this.

Thank you for the contribution, it was a big help.

Took the power driver board out to inspect the BR2 rectifier, but it doesn't look like a bad trace or that it was changed at all. BR1 was however, but I don't think that relates to my issue.

Next I took readings across D3 and D38 diodes. I think they are both bad. Going to replace them and see what happens.

Could swapping out to LEDs cause diodes to go bad?

Ok, now I'm stumped.

I replaced the 2 diodes and I had dimming work for a few minutes. Then, it stopped. So I think it is safe to assume that the LEDs installed are the reason the dimming circuit is failing.

Is there any way around switching back to incandescents to keep the dimming circuit from going bad? I like the look of the LEDs, and the benefits that come with them like less heat, etc, but I also want to enjoy the light show that the designers intended.

This is frustrating.

Thanks, Chris. That's where I found out that the two diodes I replaced were part of the dimming circuit. In another thread it was suggested to me, like Cal50 says too, that the BR2 traces were probably affected when someone replaced it. However, mine wasn't replaced and the traces have continuity to the diodes.

Like I said, when I replaced the diodes, the dimming worked for a few minutes. I'm guessing the LEDs are putting a strain on the diodes since they use a different form of dimming than incandescents do. I've only learned basic solid state circuiting so why the LEDs are doing this I can only guess. I'm sure because they need pulse modulation to dim and the system is lowering voltage instead, thats probably causing too much of an amperage load. Can anyone educate me on this?

As the machine is built, I'll probably have to put all GI lighting to incandescents if I want to have the proper lighting effects. I'll probably work on that this weekend and replace the two diodes again and see if the dimming circuit remains intact with no LEDs in the mix. If that fixes the issue then maybe I can explore building some kind of supplemental board to allow the LEDs to be dimmed so they can still be used.

I hope I can find a solution to having both the proper dimming effects and the LEDs installed because this table looks a lot better with LEDs. The whites are more fitting to the theme. Also the blues I've seen in other's tables.

Also, if I'm way off in my assumptions about any of this, feel free to educate me. I'm more than willing to learn.

Chris, forgive my inexperience, I don't understand why the dimming did work, but now has stopped. Is there some kind of safety in the MPU programming?

When I say it worked, this is what I did yesterday:

I removed the power driver board from the machine to inspect it and take readings. I had a reading on the diodes in both directions so I thought that they were faulty so I bought 2 new ones and replaced them. The new ones had the same readings in both directions as before so I guess I should've disconnected them before taking readings, but I digress. Another thing I did while the board was out was reinstall the heat sink that is over both BR1 and BR2. It was only held by screw since I've had the machine.

After that, I reinstalled the board thinking that I just wasn't going to figure this out and the only other thing I could do was change the IC chip at U6 which is a possibility from the wiki. I powered the machine back on, went into General Illumination tests and the lights dimmed to level 1 dimming as they are supposed to. The LEDs were pulsing of course. Seeing that they worked I started a game and manually started to access the Claw modes to get to Demolition Time. The first mode, ACMAG, had all of the GI lights pulsing at a consistent beat. Then when I finally started Demolition Time, I was hoping to see the lights shut off like they should, but nothing, they just stayed at their constant brightness level.

I then went back to the GI test and the lights no longer dim.

Did the MPU start working because I had it disconnected for a time period? And then a safety kick in because of the LED behavior? I was thinking the diodes went bad again since they are what I replaced to make things start working again, but since I only have one circuit with the incandescents back in, I thought I had probably broken them with the LEDs. As I said before, I'm inexperienced, but trying to learn. I appreciate your patience. And that goes for anyone helping me.

And I will be changing the lamps tonight.

Hi John,

I'm going to swap the lights out tonight.

And you are correct, I am inexperienced for sure. I did take some readings of the diodes and I read 630 in one direction and 1240 in the other. I thought since diodes should only read in one direction they were bad. I even read other diodes on the board and they all only read 600+ in one direction and open in the other.

I will be as careful as I can, but I know I'm only going to learn by doing. And by those of you with experience giving me advice.

And LEDs don't dim, but they will strobe when the machine is at the lowest dim setting, which they did after I reinstalled my board. For a few minutes.

Thank you for your reply and I will give an update when I have completed the changeover.

_{Post edited by Geocab : had to add a subject}

And I appreciate it.

Update: All GI lamps are now back to incandescents and the dimming is not working.

How do I check the traces? And I'll loosen the heat sink again and tighten, but I didn't use much pressure at all.

I'll get on this tomorrow. Thanks

Just pulled my board and I have continuity amongst the leads throughout the circuits. Every point on the bridge leads to the diodes or a capacitor, the diodes to the resistors, the resistors to where they go, etc.

No dimming after reinstalling.

Not sure where to go from here.

Oh my. After it stopped working the other day, I turned dimming to off so of course it's not going to work with incandescents. Working now!

Actually, no. It worked for the first tests. Played a game, saw no dimming. Went back to tests, now nothing. What the hell?

I just started in a new pinball league so hopefully I'll make some friends who would be willing to let me do that. Otherwise, I don't know anyone with pinball machines at the moment.

Hi guys!

It was suggested to me that my capacitors are probably bad and that is causing the dimming issue. What do you think of that possibility? I was thinking of replacing them since I'd have to take them out to test anyway, correct?

I was thinking of just the ones in the circuit before the zero cross which look to be:
C1 and C12

I have been having reset issues intermittently, but they usually go away with me pushing on connectors. I need to replace those too eventually, but I'd like to work on this dimming thing since the resetting isn't happening now.

Should I replace any other capacitors while I have the board off or any other components? Or am I mistaken and I can test the capacitors while on the board so no need to replace them if not necessary?

Ok, I won't then. I'm just desperate to try anything to fix this that I can afford. Can't buy a new board, can't send it to be fixed at the moment, and I'm capable of doing some things myself even though those things are basic.

Just to update in case someone else has tis problem down the line, my problem is solved.

I sent my board to Chris to fix a couple of my mistakes and to get my board to 100%. He fixed the dimming issue which in this case was the LM339.