Picked up a LW3 over the weekend. It has a nice playfield and looks mostly already filled with comet LED's. Currently it partially boots with (some) GI, music, no DMD, and a random coil pop once in a while. The GI looks to be a connector issue. When I fiddle with one of the IDC connectors the rest of the GI will come on. That will get re-pinned along with a trifurcon connector. The MPU is original and does not appear to have any corrosion that I can see, unless it is underneath the battery pack. Its a clean board. A couple of the other boards are aftermarket. I haven't gone further than this at this point.

I have just began looking into the various and common problem points on a DE machine as this is my first. I have headers/trifurcon connectors/pins. I plan to rebuild the flippers too. Anything unique I should throw in the parts order?

Thanks for the input gents. I will certainly check the spots mentioned. I also read about the LED lights on the MPU and need to check those at startup. I know after its on, only the 5v is lit, nothing from the other two. I will watch it to see if there is an error message next time.

PIA light flashes very briefly at startup. I do get the quick back in action callout. The boards actually look really nice. Some are new repro, power supply is a rottendog and the playfield power board is a gulf pinball. The mpu has no corrosion at all. Connectors and headers (including the 4x3 molex mentioned above) all look pretty nice as well. I have been reading through the pinwiki articles and Clay's guides. I don't have the test rom, but I was thinking about ordering that along with all the Chad 3.0 roms. I need to take a look at what I have for the display roms to make sure I order the correct chip.
Pop bumpers and drop targets all look to be in really nice shape top side.

I have 4.96 at the +5v to near cn17 on the mpu. On the power board I have voltages that all look pretty close to spot on at cn5 and cn6.

It looks like my issues is on the mpu at this point. I have the Leon test rom coming along with the 3.0 set. I grabbed a 6802 and a pia chip just in case as well.

Before replacing a coil, check the switch, diode, and connectivity. Coils are less likely to fail.

Summary of what all has been done to this LW3 I have:
Non-booting, no DMD, flaky at best GI, etc- went through the main chips, CPU, RAM, ROM. Swapped to no avail. Was about to send the MPU off when I found a random solder blob shorting two pins on the back side of the MPU. Removed that and the game booted with DMD, attract mode, etc

Now that it was booting, the trough kicker was not firing. I had voltage, coil fired when I shorted the transistor to ground. Transistor has been replaced at some point previously and I found one of the legs was not making connectivity due to a obliterated pad. I fixed that up and put in a TIP 102 since the transistor that was there was reading a little different than all the others. Then the coil was locked on. Back to beeping out the board. ChrisHibler was giving me advice along the way and suggested the 7408 upstream. I installed a socket and a new chip and we are "Back in Action!".

Big thanks to Chris.

Today I swapped the IDC connector for the GI with a trifurcon. GI is fully working.

I also put in a flipper rebuild kit from pinballlife. I bought the kit that was listed for LW3. When installed the stoke is very short on the flippers. When aligned at the holes with the mech resting on the rubber nub, the flippers only got to "flat" or even when fully raised. I did some bending work on the rubber stop end of the bracket to get some more stroke travel. I also worked on grinding off a bit of one of the coil stops to get more travel. I probably have to do a bit more to make them match. I was wondering if this one had something different, but the parts look similar to other machines that I saw pics of.
Anyone else have any weird issues with flippers?

the haf one part? Isn't that a play on Leo's accent?