Which wires give constant, ignition and ground on a 2004 Chevrolet Blazer?
On a 2004 Chevrolet Blazer, take constant power from the Red wire at the black 52-pin ignition harness plug, ignition from the Pink wire at the black 52-pin ignition harness plug, and ground to clean, bare body metal. Meter every wire first.
Meter every wire before you tap it. Colors change with trim and build date.
OBD-II port:Under the dash, driver sideBest power spot:Ignition harnessSystem voltage:12VIgnition type:Key start (this page)
Where do I get constant, ignition and ground on a 2004 Chevrolet Blazer?
Constant, ignition and accessory are at the key barrel.
Option 1 All the power
Ignition harness
Black 52-pin ignition harness plug.
Constant
Red
Black 52-pin ignition harness plug12V battery feed.
Ignition
Pink
Black 52-pin ignition harness plugHot with the key in run. Ignition 2 is White, the same color as the brake wire on this plug. Meter before you tap.
Accessory
Orange
Black 52-pin ignition harness plugAccessory.
Ground
Body ground
Bare metal under the dashNo ground wire in the guide. Never the battery negative post.
Starter is Yellow. Never tap it.
Option 2 Backup
Fuse tap
If you would rather not open the column.
Ignition
Fuse tap
Interior fuse panelBackup: a slot that is dead off and hot on.
Use an add-a-fuse.
From Fortin's install guide for the 2003 to 2005 Blazer with a key (guide 106381).
Where are the turn signal, reverse and light wires on a 2004 Chevrolet Blazer for advanced 360 multicam and video telematics installs?
Circuit
Wire color
Location and what it does
Left turnNot foundNot yet checked
Not found
Not foundWe found no source for this wire.
Right turnNot foundNot yet checked
Not found
Not foundWe found no source for this wire.
Park lightNegative -Not yet checked
White
Lt.Blue 26-pin BCM plug, bottom of center console right of the gas pedalNegative parking light. Meter it first.
HeadlightNot foundNot yet checked
Not found
Not foundWe found no source for this wire.
ReverseNot foundNot yet checked
Not found
Not foundWe found no source for this wire.
Dome lightNot foundNot yet checked
Not found
Not foundWe found no source for this wire.
Each chip shows the main insulation color with its stripe. Source: Fortin's install guide for the 2003 to 2005 Blazer with a key (guide 106381).
Where are the brake, door, speed and CAN wires on a 2004 Chevrolet Blazer for advanced 360 multicam and video telematics installs?
Circuit
Wire color
Location and what it does
BrakePositive +Not yet checked
White
Black 52-pin ignition harness plugPositive with the pedal down.
CAN dataDataNot yet checked
Purple (Class 2 data)
OBD-II port, pin 2Single wire data. Never tap it for power.
DoorsNot foundNot yet checked
Not found
Not foundWe found no source for this wire.
Parking brakeNot foundNot yet checked
Not found
Not foundWe found no source for this wire.
Vehicle speedNot foundNot yet checked
Not found
Not foundWe found no source for this wire.
Source: Fortin's install guide for the 2003 to 2005 Blazer with a key (guide 106381). Wires marked Not found were not in the guide.
Where are the fuse boxes and ground points on a 2004 Chevrolet Blazer?
Ground pointsBare body metalNever the battery negative post.
Locations from Fortin's install guide.
Where is the OBD-II port on a 2004 Chevrolet Blazer?
OBD II
Diagnostic portOBD-II port: under the dash, driver sidePlug-in GPS trackers and OBD harnesses connect here. Check the port before you plan the install.
Which years share wiring with the 2004 Chevrolet Blazer?
This page2004Chevrolet Blazer (older body).
Same wiring2000, 2001, 2002, 2003, 2005Fortin shows the same wiring for these years.
Help build this pageWant to be famous?Share a wire color, a photo or a tip for this vehicle, and your name goes on this page.
Add yoursClose▾
This page covers the 2004 Chevrolet Blazer (older compact SUV body, automatic) with a key start.
The wire colors come from Fortin's install guide, read wire by wire. Our own team has not yet metered these on a 2004 Blazer.
Written by API Signal, fleet GPS and camera installers for 35+ years across Georgia, South Carolina and North Carolina, installing every major telematics and camera brand. Every wire on this page lists its source.
Test every wire with a meter before you tap it
No wiring information is ever guaranteed. Colors and locations change with trim, options and build date, and the manufacturer can change them in the middle of a model year. We share this as a starting point for installers, and you are responsible for confirming every connection on the vehicle in front of you.
Common questions about 2004 Chevrolet Blazer wiring
What wire is constant power on a 2004 Chevrolet Blazer?
Red at the black 52-pin ignition harness plug. 12V battery feed. Meter it before you tap it.
What wire is ignition on a 2004 Chevrolet Blazer?
Pink at the black 52-pin ignition harness plug. Hot with the key in run. Meter it before you tap it.
Where is the brake wire on a 2004 Chevrolet Blazer?
White (positive +) at the black 52-pin ignition harness plug. Positive with the pedal down. Meter it before you tap it.
Which years share wiring with the 2004 Chevrolet Blazer?
2000, 2001, 2002, 2003, 2005. Fortin shows the same wiring for these years.
Help build this page
Had the panels off on one of these? Show the next installer what you found.
No one has sent photos for the 2004 Chevrolet Blazer yet, so yours could be the first. Every photo, wire color and tip we use goes on this page with your name on it, and it saves the next installer time under the dash.
1. Snap it
The plugs, tap points, fuse boxes and ground points. Phone photos are fine.
2. Send it
Tap "Add yours" at the top of this page. Your tip and your photos go in the same box.
3. See your name on it
We check every tip, then post it here "Compliments of" you, by name.
Compliments of
The installers who helped build this page.
★
Founding contributor spot: openThe first installer to confirm a wire or send photos for the 2004 Chevrolet Blazer gets their name here, and it stays here.
★
Every tip we use gets a creditThe wire you checked is marked "Checked on a vehicle, compliments of" you.
Want to be famous?
Your name, right on this page, for everyone who uses it to see. Add your tip and your photos in one box.
