Having trouble figuring this one out. Most of the insert lamps are lighting up in gameplay, in sync with the speed of the feature lamps on the backbox. Kind of looks like its in attract mode because they light up in rotating fashion. Hoping maybe there is something obvious I haven't thought of. The displays are also all missing the same digit, but its hard to say if that's connected.

Here's what I've done so far:
- Cleaned and neutralized corrosion from MPU, and installed corrosion repair kit
- swapped in a 5101 I'd purchased as a backup, but it wouldn't even boot :/ Boots up fine with old 5101
- repinned and rebuilt all connectors on the MPU and aux lamp driver, as well as J4 on the lamp driver board. I plan to do the rest of the connectors on the lamp driver board, but am waiting for a parts order.
- Tested all SCRs on lamp driver board
- Swapped U10 and U11, no change

Tested the chips on the MPU with a logic probe, and at U16 I found no signal on pins 2, 3, 14, and 15. Will be ordering a replacement for that, but not sure if that could be causing this problem.

Thanks for any advice! I do not have any spare working boards to swap in.

bump

In test mode, the insert lamps blink on and off properly

Before I did those things, the game would occasionally serve up both balls into the shooter lane.

Scratch that - the tube light strip has never worked

Ran out of ideas and need this machine to work ASAP, so I've swapped in an Altek mpu and lamp driver board. No change!
1. Wiring error?
2. Under playfield short?

What else could be the issue.

Here's a video of the game in attract, lamp test, display test, and during gameplay. Just now noticed the odd behavior during display test.

Still stuck on this! Gave it a break and finished the shop job. Game plays perfectly now, but my controlled illumination issue remains.

Here's where I'm at:

When the game boots, they work properly for a moment, until the backbox and display lights kick on.

Some lamps are permanently locked on.

They definitely seem to be getting the same data as the both the feature lamps and display. Even in the display test some lamps blink on and off in a repeating pattern.

GI ground braid is shorted to the controlled illumination braid, but I'm at a loss as to where to look next.

Power, lamp, power and solenoid boards are new boards. Sound and auxiliary lamp boards are original. I repinned all the connectors on the old boards.

All lamp sockets have been replaced.

All female board connectors repinned.

Double and triple-checked all connectors for wiring errors.

Closely inspected bottom of playfield for shorts.

Just hoping for some guidance as to a logical approach to diagnosing this problem.

Appreciate all the input guys!

Braid ≠ ground. Noted.

Pulled f5 (GI fuse), no change.

Swapped in known working lamp board, no change.

Aux. lamp board was already disconnected, no change.

Swapped alltek MPU with the original MPU, no change.

Triple checked connector at J1 for correct wiring.

Only oddity I can find is that the schematic says I should have an orange wire at A4J2-2. There is nothing there, and no orange wire of the right gauge anywhere near. Possibly related? I will investigate further as soon as I get a chance.

Probed all switches, all were pulsing (buzzing). None stuck high.

According to my manual, J2-2 should be orange with no trace and J2-11 should be orange-black. I do have the orange-black at J2-11.

FullSizeRender 12 (resized).jpg

No change with J2 and J3 unplugged

Rechecked wires at J1 against schematic, all are correct.

Same problem even if all displays are unplugged.

All switches work correctly.

During switch test, some of the insert lights blink in sync with the test tone.

Sound board already disconnected, no change.

Still stuck on this one. Any ideas?

All of these pins read high

Got it!

Checked continuity on the lamp strobe #1 line: all good
Plugged connectors back in and checked continuity between A4J1-11 and A5J4-13: no continuity

One of the pins on the strobe line was just bent in a way that it wasn't making a connection to the board (most likely due to my own poor crimping). Bent the pin out a little, reinserted, booted up, and all is well.

Thanks very much to everyone for the guidance! I started this thread 5 months ago, so you can imagine that finally having this solved is a huge relief!