I have a 1991 acura legend . I just got a new obd scanner that is both obd1 & obd2... paid almost $300 for it.. i get home and i can't find anywhere at all to connect my new scanner to anywhere in my car...? Is there anywhere at all I can use my new scanner to see why my car isnt starting..? Its cranking but not starting. I had the NEG unplugged from the battery too so it wouldnt drain the new battery I got for it... Guess i found out that I might have erased all the DTC's and error codes by doing that... is there a way to get them all back so I can know why my car isn't starting...? Any data or diagnostic connections ANYWHERE at all...?

SOURCE: obd1 scan tool will notaccess

A couple of ways to check and see if the computer is ok first:
check engine light must come onwith they in on position
The fuel pump must run for two (2) seconds with the key ON
There must be a 5 volt reference at sensors like map, TPS
Must communicate with scan tool
The ORANGE wires at the computer are you power input wires one has 12V all the time this is your KEEP ALIVE MEMORY
one is 12 with the Key on you MUAT HAVE VOLTAGE AT BOTH
Check the computers Ground most are out under the hood and are brown wires
Try the GM TAP TEST this is a factory authorized test with the computer connected and you verified all of the above SLAP the computer with the open hand firmly not too hard but firm see if anything changes,
Do not disconnect the battery you will erase all the codes!
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SOURCE: obd diagnostic

Look under the hood in the engine compartment.The emissions sticker will tell you if it is obd compliant...If it is manufactured in the u.s. since 1996 , federal laws require it to be obd compliant..I would give the manufacturer of the scanner a call to check compatability...Good Luck!!!

SOURCE: Alarm system keeps going off

I had same problem, when a door lock broke, the car thinks it has been broken into once the alarm goes off. Mine started going off randomly when this lock broke. You have to reset the alarm system, with my 1990 Acura it was reset finally by putting key in door lock and turning key back and forth 3X. In my car, it was OK to do the key in door lock cycle in the passenger side door lock, but Acura dealer told me not all Acuras will reset it via passenger side key cycling, some require driver door lock key cycling only. I was lucky since my driver side door lock was currently useless, that my car allowed it to be done by key cycle on pass. door lock. But try that and if it doesn't fix it, just call acura dealerships until someone tells you the right answer. In my situation it took 3 dealerships with 3 different answers until this was the right one for my 1990 Legend.

PS I was told you can't disable alarm since it is all integrated into the battery and starting system, but read on another post that someone disableld theirs by disconnecting the horn.

SOURCE: 95 park avenue, how do I read the obd1 codes thru the car

you have a obd2 it has 16 data link connector you have to use scanner to get codes.now the obd1 system have 12 data link connectors..the top two at far right is where you put jumper wire to retrieve code.

SOURCE: Can you disable car alarm in 1991 Acura Legend by

If it's a cheap aftermarket alarm, check for a red wire coming off the hot side of your battery with an inline fuse. If it's not, try to locate the alarm "computer" under the driver's side dash or nearby your fuse panel. You'll find a black box with a wiring diagram glued to the side, normally strapped to a wiring harness or other fixed element. If this is the type of alarm you have, you'll need to trace each wire coming from the alarm computer and unclip each fastener that's clipped to your vehicle's factory wiring. The trouble with these types of alarms is that they can get power from a number of sources (stereo, interior lights, etc.). Good luck with this one!