Blazer door lock isolation?

--I believe the relays would be internal to the BCM, with no low-current negative pulses available anywhere that you can access. If you want driver's-prirority unlock, you'll have to 5-wire it witn your own relay. You can always verify this by listening for which parts click when you operate the locks. I find that if you hold a screwdriver or other tool firmly against a particular part, you can be more sure than just doing it by ear. --Up above the parking brake, I think that's just a junction plug, not a relay bank.

Hi Chris, the relays are in a relay pack above the parking brake. I verified this today and pulled them down (what a pain). The user named brcidd was VERY helpful in sending me the GM wiring schematics for the relay pack circuit. As suspected, it has a separate relay for each: lock (all doors), unlock (driver only) and unlock (ALL doors). The problem is that the third relay mentioned above unlocks ALL the doors (which is equivalent to what happens during the 2nd push of the unlock button on the factory remote) I am too anal and dont want that...lol. So, I can just tap into the driver unlock only relay with the first unlock alarm output. The second alarm unlock output, however, will be different. Normally it would open all the door locks. I want it to only open the passenger door only. That way the driver door motor doesn't get unlocked twice needlessly. That means I will in fact have to isolate the unlock wire but only to the passenger door, not both doors as others have said. I think this should work for that: 85 - B+ 86 - 2nd alarm unlock output (-) 87 - B+ 87a - tan unlock motor wire (going to relay pack) 30 - tan unlock motor wire (going to lock motor)