http://www.bachmanntrains.com/home-usa/board/index.php/topic,7078.0.html
Run a jumper from J-1, pin 3, to J-2, pin 5.
Then run a jumper from J-2, pin 6, to J-1, pin 2.
Run another jumper, with a properly selected dcc sensitive resistor, from J-1, pin 1, to J-2, pin 4, observing proper polarity using your Grade Meter.
Now, run another jumper from J-1, pin 47, to J-3, pin 94, inserting a parallel varistor/zener combination for the specific gear ratio of the locomotive.
Make absolutely certain you cut the track on the mother board as shown in the Digital Documentation provided on page 962!
Now, run a parallel jumper from J-3, pin 37, and J-3, pin 38, to J-4, pins 90 and 91.
DO NOT connect to pin 93!
Using your ROHS compliant soldering station, remove D2 and Q4 from the mother board.
Order the parts listed on page 436 of the Digital Documentation, and when they arrive, solder them into the places you removed D2 and Q4 from.
Connect a temporary programming port to J-6, pin 88, 87, and 85. DO NOT connect to pin 86!
Pin 86 is the one-way smoke release port!
Read page 1,457 of the Digital Documentation!
Power up the unit.
When the lights stop flashing (some units may take up to 15 minutes to stabilize), plug your separately purchased port programmer into the temporary programming port.
See if you can program value 17 to high 42.
If not, the mother board is defective.
Remember, factory warranty is 90 days, and this entire scenario was designed to have you at this point on day 91.