Haltech HT-231001 Nexus Plug-In ECU – Honda EP3 (01-05) / DC5 Integra RSX (02-04)

Haltech HT-231001 Nexus Plug-In ECU for Honda EP3 (01-05) & Integra/Acura RSX DC5 (02-04)

The Haltech HT-231001 Nexus Plug-In ECU plugs directly into your factory Honda EP3 or DC5 Integra/RSX wiring harness and sits neatly in the factory ECU location — no rewiring required. It fully supports vital OEM functions while unlocking modern standalone engine management, wireless Wi-Fi tuning via the Haltech Connect App, and serious race-focused functionality.

Vehicle Compatibility

• Honda Civic Type R EP3 (2001–2005)
• Honda Integra / Acura RSX DC5 (2002–2004)

Supports manual transmissions only – factory 5 or 6 speed manual.

Key Features

• Drive By Wire throttle support
• Single channel onboard wideband control (supports LSU4.9/NTK)
• Built-in Wi-Fi for wireless tuning and diagnostics
• 4-channel onboard oscilloscope
• 128MB onboard data logging
• Flex Fuel compatible
• Closed loop O2 control
• Knock control
• Long term fuel and ignition learning

OEM Plus & Race Functionality (via Auxiliary Connector)

• O2 control, Flex Fuel, oil pressure and fuel pressure sensing
• CO2 boost control
• Race timer
• Advanced torque management
• Launch control
• Nitrous control
• 2 x half bridge outputs, 4 x digital pulsed outputs, 4 x synchronised pulsed inputs
• 1 x onboard wideband, 2 x sensor ground, 2 x 12V output, 2 x 5V output

What's Included

• Nexus Plug-In ECU
• Air temperature + wideband expansion harness, 2.5m (8')
• Air temperature sensor (1/8" NPT)
• Aluminium bung for air temperature sensor
• Mounting brackets and hardware
• 2.5m vacuum hose and T-piece
• Haltech USB-C cable
• Quick start guide

Supported OEM Functionality

• VTEC solenoid
• VTC solenoid
• IMRC (dual intake runner system)
• Serial communication with the Multiplex Control Unit
• Coolant temperature display (dash)
• Battery warning light (dash)
• A/C request signal (climate control)
• Serial communication with the immobiliser

Why Upgrade to the Nexus Plug-In ECU?

Rather than stripping out your factory harness, the Nexus Plug-In ECU drops straight into the OEM connector and location on your EP3 or DC5, giving you a clean, reliable install with the tuning depth of a full standalone ECU. It's a genuine step up from the ageing factory Honda ECU for street, track, and drift-focused K-series and Honda builds.

Frequently Asked Questions

Will this fit both the EP3 and DC5?
Yes – the HT-231001 is designed for the Honda Civic Type R EP3 (01-05) and Integra/Acura RSX DC5 (02-04).

Does it support automatic transmissions?
No, this ECU supports manual transmissions only (factory 5 or 6 speed).

Can I tune it without a laptop?
Yes – it connects via Wi-Fi to the Haltech Connect App for setup, tuning, and live monitoring from a smartphone, as well as NSP software.

When will this be available?
This is a pre-sale item, expected to ship mid-July 2026.