alright so im hooking up the locks & unlocks for my remote start today. if it take a ground to the drivers door unlock wire i can get it to unlock. if i take a ground to the hatch wire i can get it to unlock. in order to get the passenger doors to unlock and all of the doors to lock i have to apply + voltage to get it to work. i thought blazers had negative locks. whats going on and how am i going to wire this up.

 

i know some gm 2003 and up need a special encoder for the locks. mines a 2000 so i thought they were negative output locks/unlocks. but i have to take + power to get the passenger to unlock.

 

I dunno if a 2000 is the same... I suppose the easiest to achieve a master lock/unlock is to feed + to the light blue wire in the lowest connector in the BCM on your heater box (brown connector) for lock. Unlock is the white wire next to it in the BCM connector. Or use the white & lt. blue wires in the master lock switch on drivers armrest. (wiretap at the BCM is easiest in my experience). That powers the lock & unlock relays in the body relay block. The light blue connector on the BCM has a lt. blue wire, connect - to that to pop the liftgate glass if you wanted that as an accessory output.

 

we tried those wires and taking them to a ground to try to trip the lock and unlock. im wondering how to get the passenger unlock and lock (which locks all the doors). the drivers unlock works if i take it to a ground. why would the passenger side not be the same. im starting to wonder if i need an interface module.

 

I really have no idea and this may be a stupid suggestion; but did u ground it 2 times consecutively? u have to hit the oem key fob once to unlock the drivers door and twice consecutively to get he pass doors to unlock

Anyhow, my real reason for posting was to ask about passlock. How did u disable or override passlock to install the starter? Ive had a remote starter layin around for years but i dont want to buy the passlock override module to be able to use it.

 

on the bypass just go with a dei 555lw bypass. there cheap on ebay. i've go the wires to the ignition and everthing else except the lock/unlocks. i have not put in the bypass yet or even tried to start it yet. im gonna get it all connected before i do that. what i mean by grounding is i took a test light and touched the drivers unlock once and it unlocked, i have not tryed doing it twice consecutively, which is a great idea i'll try. i thought theres suppose to be 3 seperate wires for the unlock/lock. 1 for the drivers unlock. 1 for all the other doors to unlock. and 1 to lock all doors. my blazer does have factory keyless.

 

You haven't said so but let me guess.... grounding the white wire in C1 (brown) connector on BCM unlocks passenger & rear doors but not the drivers. To unlock the drivers, connector C2 (LT Blue) on the BCM, looking at the connector with slot up, top row 4 wires from the left (it'll have a gry/blk and white to each side), ground that LT Green wire to unlock drivers door. (2 LT Green wires in that connector) If you have sequenced outputs use "-" outputs to that LT green wire and white wire in the brown connector to unlock all the doors.

 

so in order to get when i hit the unlock 2 times on the remote. get all passenger doors to unlock. i have to take a ground the LT green and the white wire at the same time?

 

Now we're in the realm of "it depends on your remote start" The factory one: push the unlock button once and the BCM grounds the drivers unlock relay, push the button twice and it'll ground the unlock relay for the 3 other doors. If your remote start has multiple unlock outputs you'd connect one to each relay. My Compustar unlocks all 4 doors with a single button push of the unlock button. It doesn't have a 2 push thing, you have to hold a button for 2 seconds to get the optional. Mine is programmed so it triggers all 4 doors with a simple push. Check your install manual you may have the programming option. But yeah, you have to ground both to get all 4 doors.

 

alright i'll try that. yea this remote start setup the same as the factory keyless as far as locks/unlock go