3 pulses for remote start activation

I would like to install an add-on remote start on an 03 Nissan Maxima. The remote start requires 3 neg pulses within 5 seconds. The door locks are activated by a negative pulse but the SMART entry system only allows a single pulse--once the door is locked (after 1 pulse) no more pulses are delivered to the lock motor. Can I diode isolate the lock and unlock neg activation wires and directly connect both diodes to the remote start activation wire (for a lock-unlock-lock sequence), or do I need to use a relay that is diode isolated from the 12+ wires (on the lock motor) in order to deliver a sufficient neg pulse to the activation wire (again requiring the lock-unlock-lock sequence)?

First choice should work fine. Just make sure the band on the diodes faces the lock/unlock wires.