Negative trigger to constant reverse polarity

Hi guys! Got a project that needs some know how please? I've picked up a keyless entry system I'm linking up to some electric deadlocks to secure the rear of my van, works great! I'm needing to link it somehow to a linear motor, I've tried it with the motor but it only moves it fractionally both ways ( lock/unlock) I'm guessing it only holds the constant + and - briefly and long enough for a solenoid but not a motor such as the linear? I was thinking of the two relay door locking setup which gives reverse polarity as the keyless unit also supplies a - out trigger? Thoughts please? Tia

Ok I wired up the relays as in two wire reversal and again it only moves the motor briefly in either direction, I think I need another relay or two to conver mom to constant? Tia

Got me stumped! no one?

There was a jumper on the keyless unit to change supply from 1 second to 5, all fixed :-)