THE XING RESTR AT SUZZI ON THE ARR TO LAX RWY 25L IS CROSSED 500 FT LOW DUE TO DISTR AND LACK OF FAMILIARITY WITH THE OP OF NAV AND LNAV PROCS ON THIS ARR.

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DURING APCH TO RWY 25L AT LAX; COPLT WAS FLYING; I WAS MONITORING. THIS APCH IS VERY COMPLICATED WITH MANY STEP-DOWN FIXES WHILE TRACKING LOC AND USING LNAV OR VNAV. AFTER PASSING ARNES INTXN AND HEADING TOWARDS SUZZI INTXN; COPLT WAS HIGH ON PROFILE. WE WERE USING VNAV AND LOC TRACK AT THIS TIME. ACFT SPD WAS ACCEPTABLE AT THIS TIME OF 230 KTS AND SLOWING. BECAUSE WE WERE A LITTLE HIGH ON PATH COPLT SELECTED APCH MODE WHICH CAPTURED GS. THIS CAUSED ACFT TO PITCH OVER AND ACCELERATE TO 250 KTS. I POINTED OUT THE INCREASE IN SPD. COPLT TOOK IMMEDIATE ACTION AND DISCONNECTED APCH MODE AND SLOWED ACFT USING SPD BRAKES AND FLAPS. AT THIS TIME COPLT ASKED WHAT ALT WERE WE SUPPOSED TO CROSS SUZZI AT. I CHKED AND IT WAS 9000 FT; WE CROSSED SUZZI AT APPROX 8500 FT. THIS WAS DUE TO ENGAGING GS AFTER ARNES. GS WILL TAKE YOU BELOW STEP-DOWN FIXES ON APCH TO RWY 25L. DUE TO COMPLEXITY OF APCH VNAV SHOULD BE USED DOWN TO 3200 FT TO CAPTURE GS OR MANUALLY FLY ACFT TO EACH FIX AND ALT. SPD CTL IS VERY IMPORTANT ON THIS APCH. I WAS VERY BUSY DOING CHKLIST AND TALKING TO ATC WHILE THIS OCCURRED. I DIDN'T REALIZE IN TIME THE SIGNIFICANCE OF FOLLOWING GS ON THIS APCH PRIOR TO 3200 FT.