The ARB CKMTA12 twin compressor is one of the most popular high-output on-board air systems for 4WDs in Australia. With its dual motor design and strong airflow, it dramatically reduces tyre inflation time - but installing it correctly is critical.
This guide walks through mounting, wiring and setup considerations so your ARB twin compressor performs reliably in harsh Australian conditions.
Before You Start - Planning the Install
The ARB twin compressor:
- Draws significant current
- Generates heat under load
- Requires adequate space
- Must be mounted securely
Before installation, confirm:
- Available mounting space (under bonnet or canopy)
- Cable path from battery
- Fuse location
- Ventilation clearance
Planning prevents voltage drop issues and overheating later.
Step 1 - Choosing the Mounting Location
The CKMTA12 can be mounted:
Under the Bonnet
Most common setup.
Advantages:
- Easy battery access
- Clean factory-style install
- Permanent on-board system
Considerations:
- Heat management (avoid turbo/manifold areas)
- Space clearance
- Engine bay ventilation
ARB and aftermarket brackets are available for many popular 4WD models.
Canopy or Rear Storage Area
Suitable for:
- Touring builds
- Drawer systems
- Dual battery setups in the rear
Ensure:
- Adequate ventilation
- Secure mounting to prevent vibration damage
- Protected cable routing
Step 2 - Mounting the Compressor
The twin compressor must be:
- Mounted flat and secure
- Bolted to a stable surface
- Isolated from excessive vibration
Use:
- High-tensile bolts
- Lock nuts or thread locker
- Proper bracket systems where available
Do not mount loosely or directly to thin sheet metal without reinforcement.
Step 3 - Wiring the ARB Twin Compressor
This is where many installs go wrong.
The CKMTA12 draws high current under load, so proper cable sizing and fuse placement are critical.
Key Wiring Principles:
- Run directly from the battery
- Use appropriately rated cable
- Install fuse close to battery
- Ensure solid earth connection
Voltage drop can reduce compressor performance and increase heat.
If your vehicle runs a dual battery system, ensure the supply battery can handle compressor draw without excessive drop.
(We cover cable sizing and voltage drop in detail in our ARB compressor wiring guide.)
Step 4 - Fuse & Relay Placement
The compressor kit includes relays and fuse protection, but placement matters.
- Main fuse should sit as close to battery positive as possible.
- Keep wiring runs neat and protected.
- Avoid routing near sharp edges or heat sources.
This protects both your compressor and your vehicle’s electrical system.
Step 5 - Air Line & Hose Setup
Once mounted and wired:
- Install outlet fittings securely.
- Use thread sealant where required.
- Check for air leaks before final tightening.
- Connect pump up kit or quick connect couplings.
If running air lockers, ensure correct plumbing layout and routing.
Step 6 - Testing the System
Before closing up:
- Start vehicle.
- Activate compressor.
- Check voltage at battery under load.
- Listen for abnormal vibration.
- Inspect for air leaks.
- Confirm pressure switch operation.
Let the compressor run briefly to ensure thermal cutoff does not trigger prematurely.
Heat Management Considerations
Twin compressors generate heat - especially during extended use.
Avoid:
- Enclosed, unventilated compartments
- Direct exposure to exhaust heat
- Mounting near turbo components
Heat shortens lifespan and reduces efficiency.
Professional Install vs DIY
The ARB CKMTA12 is DIY-installable for experienced owners with solid 12V knowledge.
However, professional installation is recommended if:
- You’re unsure about cable sizing
- Your engine bay space is limited
- You’re integrating lockers
- You’re running complex dual battery systems
Incorrect wiring can cause performance issues or electrical faults.
Common Installation Mistakes
- Undersized cable
- Poor earth connection
- Fuse mounted too far from battery
- Mounting without airflow
- Loose brackets leading to vibration damage
Avoid these and your compressor will perform reliably for years.
Final Thoughts
Installing an ARB twin compressor properly isn’t just about getting it working - it’s about ensuring:
- Maximum airflow performance
- Minimal voltage drop
- Long-term reliability
- Safe operation
The CKMTA12 is a serious piece of 12V equipment. Treat it like one.
When installed correctly, it transforms how efficiently you air up after beach runs, track days and remote touring.
Installation & Electrical Disclaimer
The information provided in this guide is for general educational purposes only. Vehicle electrical systems, battery configurations, cable sizing requirements and mounting conditions vary significantly between vehicles and setups.
Battery Force does not accept liability for damage, injury, loss or faults resulting from the installation or use of products based on this guide. Always consult a qualified auto electrician or professional installer if you are unsure about any aspect of your installation.
