I picked up an MIJ Kramer Focus 3000 a couple weeks ago Supposedly with the original pickups but the wiring was really screwy and not original so I'm getting it back to a more traditional wiring scheme. Before using Duncan pickups, Kramer's supposedly came with Schaller pickups. Not sure if this model did or not. According to what I'm finding, in multiple spots on the internet, Schallers used white, green, brown and yellow. Anyone have a clue what pickup I happen to have..and which lead is which? I have an extra JB and Screamin Demon to put in there if the pickup stinks regardless, but I'd like to give this one a go and see how it sounds.
Don't know what pickup that is but if you have a multimeter (you should get one if you don't), set it to read ohms or Kohms and connect one of its leads to any wire on the pickup.(Looks like you'll need to strip some of the insulation off of the end, judging by the pics) Take the other meter lead and touch the other wires until you get a reading on the meter. The pair that gives a reading should be for one of the coils. The remaining pair should be for the other coil. Verify this by connecting the meter to the other two pickup wires and see if you get a reading. You should. Take one pair of wires and tape the bare wires at the end to your guitar cable. The end of the cable should have 2 silver parts (one big, on little) separated by a black band. Tape one wire to each silver part. Plug the cable into the amp and turn the volume down low to start.Tap on the polepieces on the pickup coils with something metal (screwdriver) and you should hear noise from the amp when you tapping on the coil for that pair of wires. Also.....I've usually seen the humbucker oriented so that the coil that has the screws is closest to the bridge but it's not a rule. Depends on the polarity and wiring. Is it a 5-way switch? This should at least get you closer to finding out what you're up against. Good luck. Check here too: https://www.youtube.com/results?search_query=humbucker+pickup+identification
Might be a humbucker from an Electra MMK45? http://www.rivercityamps.com/electraforum/viewtopic.php?f=26&t=6621 Disregard that resistor color code (012345....) stuff.