Just got my blazer and was unfortunate to get it without OEM RKE.
So I got a new Autopage RF-225A for $20.00 on ebay. Thinking I should have no issues installing this as I installed a keyless entry on my mother's 2000 Jimmy.
Not so much.... install instructions are a little short, but able to figure some out. I stumbled across this site and was amazed at how helpful everyone seems to be. Any helps in filling in the blanks would be great.

H1: Main 5 pin harness:
1. Red/White Wire: Parking Light Relay Input = Connect to +12v ?
2. White Wire: Parking Light Relay Output = Brown Wire @ BCM lt Blue plug
3. Black Wire: Ground to Vehicle FRAME = Ground
4. Brown Wire: Positive output to Siren = dont have siren so N/A ?
5. Red Wire: +12v To Constant Battery Source = Red Wire Ignition Harness

H2: 7 Pin Mini Connector Wire Harness:
1. Violet Wire: Zone 3 / Positive Door Pin Switch = ?
2. Brown/White Wire: (-) 200mA Horn Output = Black (-) Steering Column
3. Blue Wire: Zone 2 / Instant Trigger Ground = ?
4. Green Wire: Zone 3 / Negative Door Pin Switch Input = ?
(Picture attached for next 2 wires)
5. Yellow Wire: Zone 5 / To Ignition Switch +12v = ? (used for starter kill?)
6. Orange Wire: 200mA Grounded when armed = ? (Used with relay to 5)
7. Grey Wire: (-) 200mA Programmable Output = (Used for 3/2 Step Unlock)

Now for the Unlock Connection I think I have figured out its the "2 Step Door Unlock wire connection for positive switched door locks" (picture attached)
Or is there an easier way of attaching:
H3: 3 Wire connector
1. Blue Wire: Door Unlock = White (TYPE A) @ BCM Brown plug
2. Red Wire: +12v = N/A unused
3. Green Wire: Door Lock = Light Blue (TYPE A) @ BCM Brown plug

Seems in the picture provided you would need 3 relays all connected along with 3 wires from brain and multiple inputs of +12v.

Also which wire is used for the trunk release (or rear glass for blazer)?

If anyone could help me fill in the ? I would be greatly appreciated.

 

Sorry, I don't have help to offer on this.

Adding OEM RKE would be so much simpler. I did it in 45 minutes for less then $25.

https://blazerforum.com/forum/showpo...02&postcount=3

 

So you was able to get the RKE, BCM, Airbag Module and FOBs for $20-30?

 

Okay update on wiring

H1: Main 5 pin harness:
1. Red/White Wire: Parking Light Relay Input = Connect to +12v ?
2. White Wire: Parking Light Relay Output = Brown Wire @ BCM lt Blue plug
3. Black Wire: Ground to Vehicle FRAME = Ground
4. Brown Wire: Positive output to Siren = dont have siren so N/A ?
5. Red Wire: +12v To Constant Battery Source = Red Wire Ignition Harness

H2: 7 Pin Mini Connector Wire Harness:
1. Violet Wire: Zone 3 / Positive Door Pin Switch = N/A Use 4 instead
2. Brown/White Wire: (-) 200mA Horn Output = Black (-) Steering Column
3. Blue Wire: Zone 2 / Instant Trigger Ground = Hood or trunk pin
4. Green Wire: Zone 3 / Negative Door Pin Switch Input = the DRIVERS DOOR is a TAN (-) PURPLE Plug, Pin B4 and the PASSENGER DOOR is a ORANGE (-) PURPLE Plug, Pin B2. The REAR DOORS and HATCH use the same wire a DARK BLUE/WHITE (-) LIGHT BLUE Plug, Pin B11. When connecting to an ALARM SYSTEM, use all 3 wires and DIODE ISOLATE.
5. Yellow Wire: Zone 5 / To Ignition Switch +12v = Not using Starter kill ATM
6. Orange Wire: 200mA Grounded when armed = Not using Starter kill ATM
7. Grey Wire: (-) 200mA Programmable Output=Black Wire @ BCM Purple Plug

H3: 3 Wire connector
1. Blue Wire: Door Unlock = White (TYPE A) @ BCM Brown plug
2. Red Wire: +12v = N/A unused
3. Green Wire: Door Lock = Light Blue (TYPE A) @ BCM Brown plug

Someone correct me if I am wrong on anything please.

 

Yes. YRMV, but I spend alot of time at the salvage yard, so they cut me a verrry good deal.