IO 12 Expander Box - 2.5m/8ft Flying Lead Harness Only Length: 2.5m (8)

Overview

The Haltech IO 12 Expander Box flying lead harness bridges your ECU to the IO 12 Expander module, delivering clean power and CAN communication over 2.5 metres of properly shielded cable. Essential for mounting the expander box away from the ECU whilst maintaining reliable data transmission and avoiding electrical interference in complex builds.

Technical Specifications

• Part Number: HT-049902
• Cable Length: 2.5m (8 feet)
• Compatibility: IO 12 Expander Box (A or B variants)
• Communication Protocol: CAN ID compatible
• Construction: Shielded multi-core cable with moulded connectors

Why You Need This

The IO 12 Expander Box transforms how you handle auxiliary outputs in complex builds — radiator fans, fuel pumps, nitrous solenoids, boost control, lighting circuits — but positioning matters enormously. Mount it too close to the ECU and you're cramped for space and routing. Too far with inadequate cabling and you'll get voltage drops, CAN communication errors, or worse — intermittent faults that only show up under load or vibration.

This flying lead harness solves the positioning puzzle perfectly. In engine bay swaps like LS conversions into BMWs or 2JZ builds in drift cars, you often need the ECU protected in the cabin whilst the IO 12 box lives closer to the ancillaries it's controlling. The 2.5m length gives you genuine flexibility — ECU under the dash, expander box in the engine bay, or split between cabin and boot in complex multi-stage nitrous or sequential turbo setups. The shielded construction prevents the CAN communication gremlins that plague cheaper extension solutions, whilst the moulded connectors eliminate the connection failures we see with DIY splice jobs.

ECU & System Compatibility

Compatible with the full Haltech Elite and Nexus range when paired with the IO 12 Expander Box (A or B variants). Works seamlessly with Elite 550/750/1000/1500/2000/2500 and Nexus R3/R5 systems. Contact our team to confirm optimal routing and positioning for your specific chassis and ECU mounting location.

What's in the Box

• 2.5m shielded flying lead harness with moulded connectors
• Haltech technical documentation

Complete Your Build

This harness requires the IO 12 Expander Box itself to function — most customers order both together for complete auxiliary control expansion. Consider our pre-wired engine harnesses if you're doing a complete EFI conversion, as we can integrate the IO 12 positioning into your overall harness design. Our team stocks the complete range of Haltech expansion modules and can advise on optimal system architecture for your build before you order.