Hello all...New guy here

My friend is working on a 1991 Nissan Maxima. He is trying to fix the power locks but cannot locate a wiring diagram for this type of lock system. It has both theft deterrent and keyless entry (touchpad). However, this power lock system uses no sub-switches and all of the wiring diagrams for this vehicle are for the system that uses subswitches (including ALLDATA). Does anyone know where a diagram for the non-subswitch power lock system can be obtained. Did a later year Maxima use this system? Any help would be appreciated