You can use the numberpad on the door to open the trunk. Not too sure if the 89 had it or not. anyways, lock your doors then unlock with the combination, after unlocking with combination push the last number 5/6 i believe and this will open your trunk. Press the next button and it should unlock the back doors, and the next does the passenger door. then to lock press the last 2 buttons together and this will lock all doors.
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Gid
'92 Blue
Stage IV package: Stg 2 cams,UDP, BB butterflies,EH intake, 68mm TB,80mm MAF,cold air snorkel,LPM,SS ypipe and catback,K&N air,Tokiko and Eibachs, Hirevs racing clutch,
Aluminum flywheel (8lbs.),
26mm rear sway bar,
17" rims, scorcher T/A (yellow) 245-45