Haltech NEXUS S3 Plug-n-Play Adapter Harness – Mitsubishi EVO 4–8 (EVO IV–VIII) & 2G DSM | 4G63 | HT-186332

The Haltech HT-186332 is the plug-n-play adapter harness that connects the Haltech NEXUS S3 standalone ECU to the factory wiring harness of the Mitsubishi Lancer Evolution IV through VIII and second-generation DSM (1995–1999 Eclipse GST/GSX, Eagle Talon TSi, Plymouth Laser RS Turbo) — all 4G63-powered applications. The adapter harness plugs into the factory ECU connector on the vehicle side and connects to the NEXUS S3 on the ECU side, eliminating the need for custom wiring and enabling a clean, reversible standalone ECU installation. The NEXUS S3 ECU is sold separately — this listing is for the adapter harness only.

What the PnP Harness Does

A plug-n-play adapter harness is the critical interface between a standalone ECU and a vehicle’s factory wiring. Without it, installing a standalone ECU requires either building a complete custom harness from scratch or extensively modifying the factory harness — both time-consuming, expensive, and potentially irreversible. The Haltech PnP harness uses the factory ECU connector on the vehicle side, so the factory harness is left completely intact and unmodified. On the ECU side, it connects directly to the NEXUS S3. The result is a clean, professional installation that can be reversed to the factory ECU if needed — and that eliminates the wiring complexity that is the primary barrier to standalone ECU installation on the 4G63 platform.

Haltech NEXUS S3 — ECU Overview

The Haltech NEXUS S3 is Haltech’s mid-range standalone ECU — a full-featured engine management system with advanced fuel and ignition control, onboard wideband O2 control, CAN bus connectivity, and extensive data logging capability. It is designed for modified and high-performance engines where the factory ECU’s limitations — fixed fuel maps, limited boost control, no support for upgraded injectors or sensors — prevent the engine from being tuned to its full potential. On the 4G63 platform, the NEXUS S3 provides the engine management foundation for serious power builds — supporting large injectors, aftermarket boost control, flex fuel, and the precise fuel and ignition mapping that high-boost 4G63 builds require. The NEXUS S3 ECU must be purchased separately.

Key Features

• Direct Plug-n-Play Installation: Connects to the factory ECU connector on the EVO 4–8 / 2G DSM harness — no cutting, splicing, or permanent modification to the factory wiring. Clean, reversible installation
• EVO IV–VIII and 2G DSM Coverage: A single harness covering the full range of 4G63-powered EVO generations (EVO 4 through EVO 8) and the 2G DSM platform (1995–1999 Eclipse GST/GSX, Eagle Talon TSi AWD, Plymouth Laser RS Turbo) — all sharing the same 4G63 engine architecture and ECU connector family
• Haltech Quality: Manufactured by Haltech — one of the most respected standalone ECU manufacturers in the performance and motorsport industry, with decades of experience in engine management systems for high-performance applications
• Required for NEXUS S3 PnP Installation: The adapter harness is required to use the NEXUS S3 as a plug-n-play replacement for the factory ECU on these platforms. Without it, a custom harness build is required

Fitment

• Mitsubishi Lancer Evolution IV (EVO 4) CN9A — 4G63T (1996–1998)
• Mitsubishi Lancer Evolution V (EVO 5) CP9A — 4G63T (1998–1999)
• Mitsubishi Lancer Evolution VI (EVO 6) CP9A — 4G63T (1999–2001)
• Mitsubishi Lancer Evolution VII (EVO 7) CT9A — 4G63T (2001–2003)
• Mitsubishi Lancer Evolution VIII (EVO 8) CT9A — 4G63T (2003–2005)
• Mitsubishi Eclipse 2G GST / GSX — 4G63T (1995–1999)
• Eagle Talon 2G TSi AWD — 4G63T (1995–1998)
• Plymouth Laser 2G RS Turbo — 4G63T (1995–1996)

Verify fitment for your specific chassis and ECU connector variant using Haltech’s fitment guide before ordering. Some EVO variants may have market-specific wiring differences. Professional installation and ECU tuning by a Haltech-experienced tuner are required — a standalone ECU requires a custom base map and dyno tune for safe and optimal operation.

Specifications

• Brand: Haltech
• Part Number: HT-186332
• Compatible ECU: Haltech NEXUS S3 (sold separately)
• Type: Plug-n-Play Adapter Harness
• Application: Mitsubishi EVO IV–VIII (4G63T) / 2G DSM (4G63T)

Important: This listing is for the adapter harness only — the Haltech NEXUS S3 ECU is sold separately. A standalone ECU installation requires professional installation and a custom base map and dyno tune by a tuner experienced with Haltech systems and the 4G63 platform. Do not attempt to run a standalone ECU without proper tuning — an incorrectly tuned ECU can cause engine damage.