Two-Rail DC Directional Lighting Circuit Rail A (+) DC in Rail B (−) DC in R1 1 kΩ R2 1 kΩ LED1 Forward (white) LED2 Reverse (red) Tap from motor brush leads (not from track directly) Forward: Rail A = (+) → R1 → LED1 lights. LED2 blocked. Reverse: Rail B = (+) → R2 → LED2 lights. LED1 blocked. Use 2.2 kΩ resistors for dimmer, more prototypical headlights.