Yes.

No.

It is because 3C and 4C are working.

Just pick one to start with, put game in solenoid test and lock on a flasher that doesn't work. Check orange wire on flasher bulb socket for a pulsing 30 volts dc. Then check the other wire on the socket for voltage, no volts = bad bulb. If this is good then check for voltage at the resistor board for this bulb, wire from the bulb should be the same color on the resistor board. Check for voltage on both sides of the resistor. Voltage only on one side = bad resistor. No voltage at the resistor check for cracked header pins on the resistor board. If this is all good then the same colored wire goes to the aux power supply on J5. Check for cracked solder joints on the header pins. And lastly it goes thru the larger diodes D-31 thru D-46 on the aux power supply, a diode could have burnt open causing the bulb to not flash.

That fuse is for 50 volts coils, I think it is the left flipper coil. Most of the time a maladjusted EOS switch.

I think there fine.

Was this steady or did it pulse with the A/C relay as it should?

For 5C ducks there are two bulbs on the p/f, can you take a pic showing both bulbs at the same time with a label on each so I can see if they are wired in parallel or series? Also did you rewire any thing with these bulbs?

Bulbs sockets are in parallel as they should be. Did you have any of the boards out of the back box? Can you put the game in solenoid test and lock it on A/C relay, check the orange wire for dc volts again. Does it pulse or is it a steady voltage?

Was this board in the game before the P/F swap? Are the jumpers W4 and W5 installed correctly.

Disconnect J11 on the aux power supply. Turn on game and measure the voltage on J11 pin 1 and 4. Then check pin 9. What do you get?

I can't find any pics of the resistor board for this game. Can you take one and post it?

I don't know which connector with the black wires goes to the lamps. That being said you should disconnect both connectors with the black wires. Install a new bulb and retest it. The bulb should not work, but if you have pinched the wire somewhere and it grounded the lamp will light with out the dropping resistor and burn out quickly.

Orange wire comes from the A/C relay. When the relay is turned on power is supplied on the orange wire. Manual says 25 volts but is more like 36-37 volts. The orange wire is daisy chained to flashers 1c-8c. All other flashers are powered by a red wire and is always powered. The black wire then goes to the resistor board, thru a resistor and then to the cpu board where it is grounded by a TIP transistor.

I have not seen a cement resistor drop in resistance before, but anything is possible. If the resistance drops the current flow thru the bulbs will go up and they will burn out.

The cpu energizes the A/C most of the time, some game the flashers turn on in attract mode.

Is this because the bulb filament is burnt out. Install a good bulb and you should have voltage on both wires.

The resistor board is reducing the power from wire the black/color wire. So you were working on 5c flashers which is black/green wire. Look at the connectors on the flash board for the black/green wire, which pin is it. Remove the connector and check for continuity from this pin to the resistor leads on the board. Now you know which resistor it is, then check the resistance of this resistor and compare it to a working flasher circuit resistor.

Check the resistance which the connectors removed from the board.

I agree. That's why you should check for cracked header pins on the connectors on the resistor board. Also measure the resistors on the resistor board and check for cracked solder joint on the resistor leads.

Correct.

The Tip transistor on the CPU board. It grounds the black wire completing the circuit.

Check the fuse that powers the orange wire, it may have burnt also.

On page 29 of the manual it has a diagram of the A/C relay and how it works in the game.

Glad to help.