Curiosity has gotten the better of me, so before I break anything, I'm going to ask here.

I currently have my EM machine in 3 pieces. I want to test the General Illumination circuit as I have just rebulbed the head board. So, here is what I have...

The power supply and relay bank board
The head board full of bulbs and score reels
The wiring harness from the back of the playfield.

Can I plug the head board into the relay bank without the playfield wiring attached? Will it light the bulbs in the head?

Yes.  Without the playfield connected you can still plug the machine in and it should light the GI in the head.

Quoted from sentinelking

Curiosity has gotten the better of me, so before I break anything, I'm going to ask here.

I currently have my EM machine in 3 pieces. I want to test the General Illumination circuit as I have just rebulbed the head board. So, here is what I have...

The power supply and relay bank board
The head board full of bulbs and score reels
The wiring harness from the back of the playfield.

Can I plug the head board into the relay bank without the playfield wiring attached? Will it light the bulbs in the head?

Hey guys,

Just tried it.... no lights. Is there a certain set of conditions that have to exist before it lights? Like a boot sequence?

Which make & machine is it ?

Typically you do not need the PF connected to light-up the head,
however most machines definitely need to have their Lock relay
(also sometimes the tilt-hold relay) operated to light-up the GI lamps...

Other makes (such as Gottlieb EMs) need to coin-op and start the
reset sequence to light-up the GI.

Make sure the slam tilt is not on, and that the normally closed
contact for the kick-off switch (if equipped) is properly closed.
Make sure that the connectors cabinet mech to head are clean.

If it is a Bally EM, make sure that the fuse holders are putting a
good pressure on the fuses - many times these need replacement.
Check the fuses with an ohmmeter - out of circuit. They might look
good, but one may not be...

Cheers,
- Sylvain.

I didn't have any of the coin mechanics or the plumb bob hooked up to it, so not much happened. I'm going to try it again after I get it closer to completed.

Thanks for your advice.