Hello, I’m having Some weird issues with my revenge from mars, the pc and parallel connection are working fine (also tried with spare Nucore system) but no success. The PC seems to boot into the game but only 1 light is flashing -> it is actually displaying the attract mode animation.

**Things going wrong**
1. When i turn on RFM, the pc is booting and showing the correct picture on the monitor
2. After a while, the PC will connect to the power board as expected, i can see it is actually playing the “attract mode” animation but only 1 light is functioning (middle orange soucer beam)
3. None of the buttons are doing anything but it looks like the “coin door open/close switch” is actually registering by the PC.
4. The fuse leds are all of except the F111-F112-F110-F108, it seems these should only come on when the PC has booted but that doesnt seem to happen. I checked/replaced all fuses and all are perfectly fine, they also dont blow when turning on the system

**Possible cause**
- I might or might not have accidently connected the 50v rail to one of the switches while trying to repair a pop bumper

**Things i tried**
- Checked the computer + parallel Cable, everything is fine here, also tried a Nucore system but still same behavior.
- Reseated EVERYTHING in PC/PowerBoard & Playfield probably multiple times, also replaced all fuses.
- In the center of the board there are 2 measuring points just left of LED17 for +20V,+50V +12V, the readings here are 24V, 80V and 15V DC ?! these seem a bit high or is it normal because there is no load?

**Still need to try / Need help with these**
- How would I check if the correct voltages from the transformeren are present? The connector is a big one and i cant seem to find a real pinout diagram of the transformer, also where am i suposed to put the black probe (where to attach it to common ground without blowing up everything).

**Video**
I made a video showing the current behavior when turning on the machine:

Update:
narrowed down the issue to the 16VAC rail not being present.
https://pinside.com/pinball/forum/topic/how-to-check-transformer-voltages#post-7475424

The door is closed when booting, i open and close the door in the video. The computer actually registers the door opening and closing but the fuse leds stay unlit. i got a bit further and i think it has to do with fuse 109 not working as this one controls the relay which switches the voltages for the 8 leds right of the relay. I would like to test the transformer (16VAC might be dead) but I dont know how.

I can stick the red probe of the multimeter in the connector, i'm not really sure where to safely put the black probe to test AC voltage in RFM, It should touch the "common" wire but should not touch the DC GND, im not sure where to probe the common AC line.

I made a new post exactly asking this: https://pinside.com/pinball/forum/topic/how-to-check-transformer-voltages#post-7475424

Just checked voltages on the connector on the board ->
50VAC = 58VAC (this is the same with and without the field connected)
20VAC = 19VAC
The connector coming from the field has only has 3 wires in 1,2 and 5 in my case. 3,4,6 has no wire going form the board to the field

IMG_2833 (resized).jpegScreenshot 2023-03-18 at 14.29.21 (resized).pngScreenshot 2023-03-18 at 14.32.59 (resized).png

I noticed this wire is going to the playfield and J105 is actually coming directly from the transformer.
Checking...

So i measured the J105/transfo connector:
- 18V AC Lamp Matrix A = 20.2VAC
- 18V AC Lamp Matrix B = 20.2VAC
- 51V AC Secondary = 60.4VAC
- 16V AC Secondary = 20.2VAC
- 9.8V AC Secondary = 13.3VAC

These are the voltages with the power board plugged in and disconnected. these seem a bit high altho nothing is actually connected so the higher values may be correct? any toughts?

F109 is fine, when checking the diodes, I find that most of them have a reading around 400-500, but also most of them allow voltage to passtrough in both ways?

I got the following readings from your graph,
Pinside_forum_7481546_0 (resized).png

Then i checked the conections to the rectifier:
Screenshot 2023-03-20 at 23.51.18 (resized).png

Then i checked the diodes themselves:
In the correct direction i get a reading of 335 for all diodes
in the incorect/blocking direction i get a reading that starts at 500 and slowly keeps increasing

?! I double checked the 59VAC on J104-4&5 that

I also noticed my J104 connector only has 3 wires in it while the scheme shows 4. the game worked perfectly before so i assume it's nothing.

Screenshot 2023-03-20 at 23.28.54 (resized).png

I noticed R186 has a value of 1550 ohm while schematics say 2K, and R291 has a value of about 1660 ohm