How to Install a Push Button Start Kit: Step-by-Step Guide

Installing an aftermarket push button start kit is one of the most satisfying upgrades you can do to your vehicle. Whether you’re modernizing a classic hot rod or adding keyless convenience to your daily driver, learning how to install push button start is a project most handy DIYers can tackle in an afternoon.

This guide walks you through every step of a push button start installation — from identifying your ignition wires to testing the finished system. We’ll use the Digital Guard Dawg iKey Premier as our reference system, but the general process applies to most aftermarket push button start kits.

See our complete Push Button Start Guide for a deep dive into how these systems work.

Safety First

Automotive electrical work demands respect. A short circuit can fry expensive modules, blow fuses, or — in worst cases — start a fire.

Disconnect the Battery

Always disconnect the negative (–) battery terminal before touching any wiring. Wait at least 5 minutes after disconnecting to allow capacitors in the airbag system to discharge. This is non-negotiable.

Understand Your Wiring

Before cutting a single wire, take photos of everything. Document the existing wiring under your dash and at the ignition switch. If something goes wrong, you want a roadmap back to stock.

Pro Tip: DGD systems like the iKey Premier are designed for non-permanent installation. No wires are cut at the ignition switch — everything connects via the included relay harness. This means you can always revert to factory if needed.

Know Your Vehicle’s Wiring Diagram

Get a wiring diagram specific to your year, make, and model. Sources include:

•             Your vehicle’s factory service manual

•             Online databases like AllDataDIY or Mitchell1

•             DGD’s vehicle-specific installation guides — Digital Guard Dawg provides detailed wiring information for thousands of vehicles and offers free phone support during installation

Step 2: Mount the Push Button

Choose a mounting location that’s both accessible and aesthetically pleasing. Common spots include:

•             Blank switch panel — Many vehicles have unused switch knockouts in the dash

•             Center console — Easy reach from the driver’s seat

•             Custom dash plate — Popular for hot rods and custom builds

•             Over the existing ignition — DGD’s Slim Line buttons are only 1/4” thick and mount directly over your factory key cylinder

Drilling and Mounting

1.          Determine button size. DGD’s billet start buttons come in 22mm or 25mm diameters with your choice of LED halo color (Blue, Green, Red, or White).

2.          Mark your drill point. Use a center punch to prevent the bit from walking.

3.          Drill with a step bit. Go slowly. A step bit gives you a clean, burr-free hole in sheet metal or plastic.

4.          Test-fit the button before committing. Make sure it sits flush and clears any components behind the panel.

5.          Install the button with the included mounting hardware. Route the button wires behind the dash.

Step 4: Connect the Relay Harness

The relay harness is what allows a push button start kit to control your vehicle’s ignition circuits without modifying the factory wiring.

DGD systems use a plug-in relay harness (36” length on the iKey Premier) with heavy-duty relays rated at 40 amps each with 220-amp in-rush capacity. This is important — the starter motor draws significant current on initial engagement.

Connection Process

1.          Plug the relay harness into the RFID module. This is a direct plug-in connection — no soldering required.

2.          Route the harness toward the ignition switch area. Avoid sharp edges, moving parts, and heat sources.

3.          Secure the harness with zip ties along existing wire looms. Keep everything neat and professional-looking.

Step 6: Connect to Ignition Wires

Now you’ll connect the relay harness outputs to the ignition wires you identified in Step 1.

Connection Method

For each ignition wire (ACC, IGN1, IGN2, Starter):

1.          Strip approximately 1/2” of insulation from the vehicle’s ignition wire at your connection point.

2.          Connect the corresponding relay harness wire using a soldered splice or high-quality crimp connector. T-tap connectors are convenient but less reliable long-term — solder is preferred.

3.          Insulate each connection with heat shrink tubing. Hit it with a heat gun until it’s fully sealed.

4.          Tug-test every connection. A loose splice under the dash will cause intermittent problems that are maddening to diagnose.

Wiring Map (Typical DGD System)

Relay Harness Wire	Connects To
Red	12V Constant (BATT)
Purple	ACC
Pink	IGN1
Green	IGN2 (if applicable)
Yellow	Starter
Black	Chassis Ground

Important: Your specific vehicle and kit may differ. Always follow the wiring diagram included with your system — not generic guides from the internet.

Step 8: Reconnect Battery and Test

This is the moment of truth. Take a breath and go through this checklist before reconnecting power.

Pre-Power Checklist

•             ☐ All connections are soldered/crimped and insulated

•             ☐ No exposed wire touching metal

•             ☐ Relay harness is fully plugged into the module

•             ☐ Push button is connected to the module

•             ☐ RFID antenna is connected

•             ☐ All wires are secured and away from moving parts

•             ☐ No tools left in the engine bay

Testing Sequence

1.          Reconnect the negative battery terminal.

2.          Don’t press anything yet. Listen for any unusual clicking or buzzing from the module. Look for smoke (seriously — if you see or smell smoke, disconnect immediately).

3.          Hold the RFID fob near the antenna. The system should recognize the fob — typically indicated by an LED flash on the module or button.

4.          Press the button once. The ACC circuit should engage. Radio, power windows, and other accessories should turn on.

5.          Press again (or press and hold, depending on your system). IGN should engage — you’ll hear the fuel pump prime.

6.          Press and hold the button with your foot on the brake. The engine should crank and start.

7.          Test the shutdown sequence. Press the button to turn off the engine.

8.          Test the RFID security. Remove the fob from range and try to start the vehicle. It should NOT start — this confirms the immobilizer is working.

Program Additional Fobs

The iKey Premier supports up to 4 RFID fobs plus 2 emergency bypass cards. Program your spare fobs now while everything is accessible. Follow the programming sequence in your installation manual.

When to Use a Professional Installer

DIY push button start installation isn’t for everyone, and there’s zero shame in handing this job to a pro. Here’s when it makes sense:

Complex Vehicles

•             Vehicles with CAN bus or multiplexed wiring (most 2008+ models) — These use data signals instead of traditional 12V wires, requiring specialized interface modules.

•             Vehicles with factory immobilizers — You may need a transponder bypass module in addition to the push button start kit.

•             Diesel vehicles with glow plug circuits — Additional wiring is needed to manage the glow plug warm-up cycle.

Comfort Level

If any of these describe you, consider professional installation:

•             You’ve never used a multimeter

•             Automotive wiring diagrams look like hieroglyphics

•             The idea of cutting into your vehicle’s harness gives you anxiety

•             Your vehicle is high-value or irreplaceable

Finding an Installer

•             Car audio/alarm shops — These technicians install aftermarket electronics daily. They’re your best bet.

•             Auto electricians — Specialists in vehicle wiring.

•             DGD’s installer network — Digital Guard Dawg can recommend experienced installers familiar with their systems.

Professional push button ignition install typically costs $150–$400 depending on your vehicle and region, on top of the kit price.

Explore DGD’s full line of automotive keyless ignition systems.

Frequently Asked Questions

Can I install a push button start kit on any vehicle?

Yes. Aftermarket push button start systems like the DGD iKey Premier are compatible with almost any vehicle — cars, trucks, hot rods, classics, and modern models. The only notable exception is select 2012+ Mercedes models with encrypted CAN bus systems.

Will a push button start kit void my warranty?

Aftermarket push button start installation should not void your vehicle warranty under the Magnuson-Moss Warranty Act. The dealer must prove that the aftermarket part directly caused the failure they’re denying coverage for. That said, DGD’s non-permanent, relay-based installation makes removal easy if needed.

How long does a push button start installation take?

For someone with intermediate wiring experience, expect 4–6 hours for a complete push button start kit install. Experienced installers can finish in 2–3 hours. First-timers should budget a full day.

Do I need to disable my factory key to use push button start?

No. Most systems work alongside your factory ignition. The relay harness handles the switching, and your original key cylinder remains functional as a backup. Some owners choose to leave the key in the ON position permanently and only use the push button.

Is an aftermarket push button start secure?

Quality systems are extremely secure. DGD uses Texas Instruments RFID technology with Dual-Frequency Dual-Encryption and over 6 billion unique codes — making electronic cloning virtually impossible. This actually adds a layer of anti-theft protection beyond what a traditional key provides.

What happens if my RFID fob battery dies?

DGD systems include emergency bypass cards (credit card-sized RFID tags) that you can keep in your wallet. The iKey Premier supports 2 emergency cards in addition to 4 standard fobs. Even with a dead fob battery, holding the fob directly against the antenna will usually allow a read.