Looking for a reliable way to power your 4WD gear without draining your main battery? Coldys specialises in dual battery installations for serious off-roaders and working tradies who need dependable power wherever they go.
We offer full dual battery system installs at our Hawkesbury workshop or via mobile service across the Hills and surrounding areas. Whether you're running fridges, lights, air compressors or tools, we’ll build a setup that suits your vehicle, your gear and how you use it.
Stay Powered Wherever You Take Your 4WD
Whether you're camping off-grid, powering tools on-site, or keeping the fridge running overnight, a dual battery setup gives you the freedom to run your gear without draining your starter battery.
We install dual battery systems built for real use — systems that perform in heat, dust, and remote conditions. From 4WD getaways to everyday work setups, you’ll have the confidence to power up and keep going.
Here’s what a professionally installed dual battery system lets you do:
- Power your gear without draining your starter battery
- Stay powered off-road — wherever you go
- Run fridges, lights and gear with confidence
- Built for fridges, lights, compressors and more
- The power setup every serious 4WD needs
- Extra power when you need it — without the risk
No guesswork. No flat starts. Just reliable, ready-to-use power wherever the job or the track takes you.
What’s Included in Your Dual Battery Installation
Every install is designed around your vehicle type, available space, and power requirements. When you book with Coldys, you get:
- Vehicle-specific battery tray installed in the engine bay or cabin (if needed)
Secondary battery connected safely to your existing system - DC to DC charger or smart battery isolator (depending on your alternator and battery type)
- Dual battery wiring kits with high-quality cabling, fuses, and heat shrink for protection
- Optional solar panel input for off-grid charging
- Neat, easily accessible mounting for components
- System tested and ready to use before handover
Choosing the Right Charging Setup for Your Vehicle
The way your second battery charges depends on your vehicle’s alternator and battery chemistry. We help you choose between:
Smart Battery Isolator (Voltage Sensitive Relay):
- Simple, cost-effective solution
- Best for standard alternators and basic setups
- Automatically connects and disconnects your two batteries based on voltage
DC to DC Charger:
- Required for vehicles with smart alternators
- Supports efficient charging for lithium, AGM or deep cycle batteries
- Allows for solar input
- Delivers better long-term battery performance
Not sure which one you need? We’ll recommend the right setup during your quote.
Mobile or Workshop Dual Battery Installation Available
You can choose to have your system installed at our Hawkesbury workshop, or we can come to you. Our mobile fitting service covers homes, worksites and job locations within a 50km radius.
We offer:
- Fast turnaround times (usually within 2 weeks)
- Clean, professional installs by experienced fitters
- Fully tested systems you can rely on from day one
Built for Your Vehicle, Accessories and Power Needs
No two dual battery installs are the same — and that’s why we tailor every setup to suit:
- Your vehicle's make and model
- The space available in your engine bay or interior
- Your accessory list – fridges, work lights, compressors, inverters, or camper trailers
- Your battery type – lithium, AGM, deep cycle
- Whether you want solar input or plan to upgrade later
From simple daily-use setups to full off-grid power systems, we build installs that work exactly how you need them to.
Why Choose Coldys for Dual Battery Installs
- Over 30 years of experience in 4WD and electrical installs
- Trusted by off-roaders, tradies, and fleet operators
- Local service with support you can rely on
- Quick lead times — no 8-week waits
Mobile and workshop options to suit your schedule
We don’t just bolt it in — we make sure everything is properly mounted, fully protected, and built to last in Aussie conditions.
Get a Quote for Your Dual Battery Installation
Tell us your vehicle, what gear you want to run, and whether you’d prefer mobile or workshop fitting — and we’ll take care of the rest.
Request a quote today and power up with confidence.
For reliable Dual Battery installations in Sydney, trust Coldys to get the job done right.
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