Which wires give constant, ignition and ground on a 2021 Ram ProMaster?
On a 2021 Ram ProMaster, take constant power from the Red/Black wire at the ignition switch, steering column, ignition from the Blue/Red wire at the ignition switch, steering column, 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:Location not confirmedBest power spot:Ignition switch, steering columnSystem voltage:12VIgnition type:Key
Power: one place
Constant, ignition and accessory are all at the ignition switch on the steering column. Ground to clean body metal.
Option 1 All power
Ignition switch
Steering column.
Constant
Red/Black
Ignition switch, steering columnAlways hot, 12V.
Ignition
Blue/Red
Ignition switch, steering columnIgnition 1, hot in run.
Accessory
Blue
Ignition switch, steering columnHot in accessory and run.
Ground
Body ground
Body metal under the dashClean, bare metal only. Never the battery negative post.
Red/Black constant and Blue/Red ignition are the same colors as on our 2019 ProMaster page.
Each chip shows the main insulation color with its stripe. Source: Fortin's install guide for the 2020 ProMaster with a key (Fortin lists it for 2020 and 2021 gas vans).
Where are the brake, door, speed and CAN wires on a 2021 Ram ProMaster for advanced 360 multicam and video telematics installs?
Circuit
Wire color
Location and what it does
StarterPositive +Not yet checked
Brown/White
Ignition switch, steering columnStarter output. Never tap it for a GPS or camera.
Body control moduleNegative driver door pin trigger.
HornNegative -Not yet checked
Brown/Light Green
Body control moduleNegative horn trigger.
Door lockDataNot yet checked
Blue/Yellow
Body control moduleMultiplexed (MUX) lock and unlock wire. Never tap it.
Rear doorsDataNot yet checked
Gray/White
Body control moduleMultiplexed (MUX) rear door status. Not a plain door pin.
BrakeNot 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.
CAN dataDataNot yet checked
Blue/Black (CAN1 high)
White/Purple (CAN1 low)
Light Green (CAN2 high)
Brown (CAN2 low)
Back of the body control moduleTwo CAN buses. Never cut or splice the CAN wires.
Source: Fortin's install guide for the 2020 ProMaster with a key (Fortin lists it for 2020 and 2021 gas vans). Turn, reverse, headlight, dome, brake, parking brake and speed wires were not found.
Where are the fuse boxes and ground points on a 2021 Ram ProMaster?
InteriorFuse panelNo fuse position for these years was found in a source. Read the lid label and meter the slot.
Ignition switchSteering columnConstant, ignition and accessory, per Fortin.
Ground pointsClean body metalNever the battery negative post.
Locations from Fortin's install guide.
Where is the OBD-II port on a 2021 Ram ProMaster?
OBD II
Diagnostic portOBD-II port: location not confirmedLook under the driver side dash first, and send us a photo if you find it.
Which years share wiring with the 2021 Ram ProMaster?
This page2021ProMaster, gas, key start.
Same wiring2020Fortin lists one guide for 2020 and 2021.
Help build this pageWant to be famous?Share a wire color, a photo or a tip for this truck, and your name goes on this page.
Add yoursClose▾
This page covers the 2021 Ram ProMaster with a gas engine and 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 2021 van.
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 truck in front of you.
Common questions about 2021 Ram ProMaster wiring
What wire is constant power on a 2021 Ram ProMaster?
Red/Black at the ignition switch, steering column. Always hot, 12V. Meter it before you tap it.
What wire is ignition on a 2021 Ram ProMaster?
Blue/Red at the ignition switch, steering column. Ignition 1, hot in run. Meter it before you tap it.
Which years share wiring with the 2021 Ram ProMaster?
2020. Fortin lists one guide for 2020 and 2021.
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 2021 Ram ProMaster 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 2021 Ram ProMaster gets their name here, and it stays here.
★
Every tip we use gets a creditThe wire you checked is marked "Checked on a truck, 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.
