3/4 down the page "A Coil doesn't Work, What To Do":
http://techniek.flipperwinkel.nl/wms11/index1.html

Here's what the LED's should be doing when the game is turned on and in attract mode:

Left LED (labeled "+5 vdc"): shows that +5 vdc is present. This LED should always be on.
Middle LED (labeled "diagnostics"): should be continually flashing.
Right LED (labeled "blanking"): shows the blanking circuit is working, and should always be on.

Because your knocker isn't working you may have more than one problem. The knocker is wired separately from the other playfield coils and should work even if the playfield is removed from the game. Have you checked the corresponding C side flash lamps on Q24, Q30 & Q32 to see if they are flashing? If they aren't and the lamps are good you have to suspect these three transistors as bad.

viperrwk

When you say you checked all visible fuses did you actually pull them out and us a DMM to check them? Visual inspection is not going to cut it.

Before you ground any tabs, all you need to do is check the corresponding flashers to these coils. If the A/C select relay is working (which you indicate it is,) if the flashers work then you know the problem isn't the drive transistors on the CPU board.

The only thing the three coils you describe have in common is that they all go through the 1P11 connector on the CPU board You can carefully examine and reseat this connector and see if it makes a difference. If it does, you probably should repin it.

Could three drive transistors go bad simultaneously? Yes. Does it happen often? No. The problem here too is that the predrivers are driven through different chips as well. Q30 is predriven by the 7408 at U19 and Q24 and Q32 are predriven by the 7408 at U20. You have to go back to the LS374 at U28 and the solenoid PIA to find something in common with these three coils. And chances are if one of those were bad you'd be having many more problems than just three coils.

You could also have bad diodes on the aux power driver board for the coils, the coils themselves could be bad or bad connections in multiple places.

Anyway, next thing to check is the flashers and see if they are working. If they are, you have to look at the connectors, wiring, diodes and coils. If they aren't working, you need to check the transistors at Q24, Q30 and Q32 with your meter.

viperrwk

Okay, so although all four coils are A/C switched, the working one (Drop Target) gets its power from the BRN wire, where as the three non-working coils get their power from the YEL-VIO wires coming off 5J12-11 and 5J12-12.

Cyclone.png

The wires I'm referring to are in the red box ... but I think your problem lies where I've drawn the blue box. Looking at this diagram, that appears to be the single point of failure.

My suggestion would be to pull the Aux Power Driver Board and retouch the related solder points on the A/C select relay and 5J12-11/5J12-12 ... or maybe just do them all while you are back there.

Before pulling the board, check with DMM for pulsed "A" bank power at pins 11&12 of 5J12 while in solenoid test. If there's no power there then go through with pulling the board.

I'm a little confused at the OPs second post that said "I've tested power to the coils, and there's approx 45v to each one."

He's getting some power, just not full power. That points to a bad connection, hence my suggestion to look at that one solder point. I didn't see any other place where it looked like a single point of failure?

I agree, I was just suggesting a test point to check before pulling the board.

For the record, on my Cyclone when I go into test (select A-Side) and hook my meter up between the knocker coil and ground, I get around 75V (this is with no load) ... so what you're reading is well below what's expected.

Agreed, it's definitely a B+ solenoid supply power problem. If it were me, I would disconnect 5P12 at this point, and compare DMM readings with Ufopinball's Cyclone in the same state, with 5P12 disconnected. That would just reduces the chances of a playfield problem pulling down the power. If they are different measurements with the connector unplugged, then it would be time to pull the aux driver board and search out the culprit. Something likely between 5J12 and the relay- the relay connections, or the relay contacts themselves are possible problems.

The term "B+" you will often see on schematics designating a high DC voltage, or supply voltage. It's actually an old school term borrowed from the days when batteries supplied plate voltage to tube amplifiers. In the Cyclone manual you will see it on the descriptive theory page about the A/C relay on page 29.

If you look at the diagram in the earlier in the thread that Ufopinball posted, you will see that 5P12 is the plug that goes into 5J12. Just so you know the lingo, the "5" prefix is the board number, then J or P to designate jack or plug, then follows the suffix which is the connector number.

Since you said you tried manually grounding the coils earlier, it's not going to be a transistor problem. The transistors enable the ground path, same as using a jumper wire from the coil terminal opposite of the supply power to the ground braid. If your power is good and the coils are good, they should fire with this simple test. If they don't, and as the readings of B+ supply voltage compared to Ufopinballs reading differently...I still still suspect a supply side problem. Did you check all the coils themselves as in the doc "What to do when a coil doesn't work" http://techniek.flipperwinkel.nl/wms11/index1.html ?

The A/C relay itself could be bad...but first the problem needs to be isolated, determined definitely to be on the interconnect board. A helpful way to do this is to substitute a known good working aux power driver board. Sometimes this is not practical, so eliminating the load/downstream coils as a cause allows you to focus on the driver board as the culprit. If you can't troubleshoot the problem out, there is also the possibility of shotgunning the problem out..such as just replacing the relay. The drawback of shotgunning is the time and money lost if your guesses are incorrect.

So, according to the power diagram I had previously posted ... this +50v power supply also feeds the flippers, as well as Sol 18 & 20 (slingshots) ... are you sure all of those are working properly?

If so, then test the voltage at fuse F4, and follow on down to 5J12-11 and 5J12-12. Let us know what your meter reads at those points.

"Before Turning the Game On: Check the Fuses" http://techniek.flipperwinkel.nl/wms11/index1.html

"Problems with Flippers" http://techniek.flipperwinkel.nl/wms11/index2.htm

Not necessarily a short. Please tell us what you checked: You said EOS, did you make sure that switch opens and closes properly by measuring with a DMM? Did you check the coil (measure with DMM?, Get hot?) Coil and mechanism move freely not binding? Did you lift one side of the diode on the coil and check it?