I have flashers firing with coils firing at the same time on my diner. In test mode this doesn't happen & a/c relay works fine & all the tests are fine. But during play various sets of flashers go off with different coil firings. Almost as if the relay is only not working during play? What could cause this?

When the flippers fire the 2 cup flashers go off. Bumpers fire the right ramp flashers, etc. It is predictable.

Yes new leds and also new led flashers I just installed. Just got the game it needed shopped so I'm unsure if it was doing it before with incandescent.

Thanks for the info!

So I did the LED mod but I still have flashers firing on bumper hits (flippers are good now). I followed the instructions perfectly, had no trouble & double checked my work. So currently when the bottom bumper & left bumper are hit, the right ramp flashers light. & when the right bumper is hit, the left ramp flashers light. Does this make any sense?

Now I did just notice my flasher resistor on coil #4 (PEPE!) is failed. So perhaps that might have something to do with it? I have order the part & replace it. Had a bunch of these at one time but they never failed on me I probably threw them out. Never throw anything out!

You are right. It may not be the LED's. I replaced the failed resistor so all flashers work 100% & also tried replacing the 4 flashers in question with incandescent (left ramp/ right ramp flashers)... & it STILL does it! So I've done the LED mod exactly as described & the bumpers are still firing off these ramp flashers. Not in test mode, only during play.
It's honestly not a bad effect & I can live with it, but I just don't like things happening that apparently shouldn't be. What else could cause this?

I couldn't find any info under the system 11

Problem solved!
So unless I'm crazy.... I think older software revisions didn't have this effect with the bumpers & ramp flashers. However, I fired up Pinball Arcade on my PC & launched the diner table. It DOES fire flashers with bumpers. Yet I've seen video online where they don't, & also I just upgraded my roms to L-4 & I don't recall noticing it before that. So I guess this is normal behavior, at least on L-4 roms.