RJ-11 Phone Wiring Normal Wiring ============= Looking at the plug with the clip down and facing away: Normal Polarity at 1st End: Black, Red, Green, Yellow Color Line Function ------ ---- -------- Black 2 Tip Red 1 Ring Green 1 Tip Yellow 2 Ring Reversed Polarity at 2nd End: Yellow, Green, Red, Black Swapped Wiring for Lines 1 and 2 (plug or receptical code) ========================================================== Looking at the plug with the clip down and facing away: Swapped Lines 1, 2: Green, Yellow, Black, Red (Note that the polarity is reversed--to accommodate the Tip and Ring positions.) Pass Through Wiring Swapping Lines 1 and 2 ========================================== Looking at the plug with the clip down and facing away: Normal Polarity and Lines 1 & 2 at 1st End: Black, Red, Green, Yellow Reversed Polarity and Lines 2 & 1 at 2nd End: Green, Yellow, Black, Red