rear hatch wiring

you guys are too good, thanks for your help. now my next question. the hatch wires are red, brown , and yellow. what feed the yellow wire? i checked red and yellow wires at pull up knobs at front seats and they had voltage,now only the red has voltage which sounds correct to me. what does the yellow wire do? maybe part of turning off motor for hatch? i replaced relay but it made no difference. any help would truly be appreciated. thanks, john

The red should always show power with the ignition in the run position. The yellow wire should only show power when the switch is closed. Then, in a perfect world, the power is distributed via the yellow wire to the motor and the hatch is released.

thank you for comment, now i will try again to get this straightn,t out.