2003 Chevrolet Trailblazer Remote Start

Printed From: the12volt.com
Forum Name: Car Security and Convenience
Forum Discription: Car Alarms, Keyless Entries, Remote Starters, Immobilizer Bypasses, Sensors, Door Locks, Window Modules, Heated Mirrors, Heated Seats, etc.
URL: https://www.the12volt.com/installbay/forum_posts.asp?tid=50945
Printed Date: May 01, 2025 at 12:21 PM

Topic: 2003 Chevrolet Trailblazer Remote Start

Posted By: talon4x4
Subject: 2003 Chevrolet Trailblazer Remote Start
Date Posted: February 26, 2005 at 11:34 PM

I would like to add a remote start to my girlfriends '03 Trailblazer and I really need some help. We already have a DesignTech AutoCommand remote start unit. The model # is 20921/V1.0/1BD/4701. I can't find a wire diagram for the remote start unit. I've checked the DesignTech website but can't find this specific unit. I've emailed them several times but haven't gotten a response. Also, for the Trailblazer wire diagram, I found an '02 Trailblazer diagram on here, will that work for an '03?? Finally, I've read about having to get the Passlock bypass, but I don't know exactly what I need. There seem to be so many options when I do a search for my vehicle on https://www.bypasskit.com/ . The trailblazer only has a keyless entry from the factory, no alarm.

Sorry for all the questions.

Any help would be greatly appreciate!! :)

Thanks!

Replies:

Posted By: talon4x4
Date Posted: February 27, 2005 at 12:15 AM

OK, I've done some more searching and it looks like the only thing I need is the PLDATA, is that correct? I also found the diagram for the RS.

So the only question I have now is, will the '02 diagram work for the '03. Ohhh, and will I need any relays??

Posted By: chris354
Date Posted: February 27, 2005 at 9:30 AM

12volts	red (x2)	+	ignition harness
Starter	yellow	+	ignition harness
Second Starter	N/A
Ignition	pink	+	ignition harness
Second Ignition	white	+	ignition harness
Third Ignition	N/A
Accessory	orange	+	ignition harness
Second Accessory	brown	+	ignition harness
Keysense	lt. green	-	ignition harness
Power Lock	use 457G or 455G module
Notes: If Directed module 457G or 455G is not available, refer to DirectFax document 1053.
Power Unlock	see power lock
Lock Motor	gray		driver door module in door
Unlock Motor	tan		driver door module in door
Parking Lights+	brown	+	driver kick panel
Parking Lights-	gray/black	-	headlight switch
Hazards
Turn Signal(L)
Turn Signal(R)
Reverse Light	lt. green	+	fuse box under rear seat
Door Trigger	gray/black	+	underdash light or driver A pillar
Notes: To avoid dome light delay, use the separate door trigger wires. The LF door is gray/black (-) at the driver door module in the door. The RF door is BLACK/ white (-) at the passenger door module in the door. The LR door is lt. blue/black (-), and the RR door is lt. GREEN/ black (-). The rear door trigger wires are at the fuse box under the left rear seat. Use all four wires and diode isolate each.
Dome Supervision	comes on with disarm
Trunk/Hatch Pin	common with door trigger wire
Notes: To avoid dome light delay, use the separate trigger wires at the liftgate module in the liftgate. The liftgate is pink/black (-), and the glass hatch is purple (-). Use both wires and diode isolate each.
Hood Pin	pink/black	-	pin switch or BCM
Trunk/Hatch Release
Power Sliding Door	N/A
Factory Alarm Arm
Factory Alarm Disarm	lt. green	-	driver door module in door
Disarm No Unlock	see factory alarm disarm
Tachometer	white	ac	blue plug, pin 49 @ PCM
Notes: The PCM (Powertrain Control Module) is on the driver side of the motor.
Wait to start	N/A
Brake Wire	white	+	brake pedal switch
Parking Brake
Horn Trigger	black or BLACK / YELLOW	-	steering column
Memory Seat 1
Memory Seat 2
Memory Seat 3

Immobilizer Bypass Module:	Required: Yes	Type: Passlock 2	Part #: 457G, 555L, or 555T
Notes: N/A

Posted By: chris354
Date Posted: February 27, 2005 at 10:16 AM

If that system only has 1 acc. which i think it does you will have to build a relay to power the second acc.

Posted By: iskidoo
Date Posted: February 27, 2005 at 10:51 AM

chris354 wrote:

If that system only has 1 acc. which i think it does you will have to build a relay to power the second acc.

I don't think you need to bother with the 2nd accessory, doesn't that just power the radio and wipers?

Posted By: iskidoo
Date Posted: February 27, 2005 at 11:25 AM

The PLDATA works very well and is very easy to use. You can also use DEI units 457G, 555L, or 555T. Don't bother with the brown 2nd accessory wire on your starter connections. It is not required for remote start.

Posted By: chris354
Date Posted: February 27, 2005 at 1:59 PM

I would go ahead and power it I know on the newer gm cars if you dont it can cause a check engine light to come later on. The diagram came from dei usually if it is listed then they recomend using it. But your right it doesn't have to be hooked up to rs.

Posted By: talon4x4
Date Posted: February 27, 2005 at 2:47 PM

Great, thanks for all the info!! I'm sure I'll be back with more questions after I get into this project! :D

Posted By: iskidoo
Date Posted: February 27, 2005 at 3:51 PM

chris354 wrote:

I would go ahead and power it I know on the newer gm cars if you dont it can cause a check engine light to come later on. The diagram came from dei usually if it is listed then they recomend using it. But your right it doesn't have to be hooked up to rs.

I think that not hooking up the 2nd ignition will cause the idiot light to come on but I could be mistaken. I usually don't hook the 2nd accessory for the simple fact that if the wipers are left on when the car it shut off, I don't want them trying to work when it's frozen to the windshield and the defroster hasn't freed them up yet. When I get in and turn the key on the radio turns on and wipers work.