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SKU: HT-186331 | UPC: 9356450015189
Haltech HT-186331 NEXUS S2/S3 Plug-and-Play Adapter Harness
The Haltech HT-186331 NEXUS S2/S3 Plug-and-Play Adapter Harness provides a fully terminated, vehicle-specific wiring solution for installing the NEXUS S2 or S3 ECU into popular performance platforms without cutting factory harnesses. This adapter connects directly to the OEM ECU connector and includes all necessary breakout leads for Haltech CAN, power, ground, ignition, injectors, sensors, and auxiliary outputs for a true plug-and-play upgrade that retains full OEM functionality while unlocking NEXUS-level tuning control.
Built with high-temperature TXL automotive wire, OEM-style connectors, and Haltech’s signature braided shielding, the harness is designed for extreme under-hood conditions and supports 1,500+ HP builds with zero voltage drop or signal interference. Pre-labeled wires and included detailed pin-out diagrams make installation straightforward for professional tuners and experienced enthusiasts.
For owners upgrading to NEXUS S2/S3 who demand the cleanest, most reliable wiring solution, the HT-186331 adapter harness is the factory-engineered, plug-and-play bridge trusted on championship-winning race cars worldwide.
Key Features
- Full plug-and-play – no cutting factory harness
- High-temp TXL wire with braided shielding
- OEM-style connectors and pre-terminated ends
- Supports NEXUS S2 & S3 ECU installations
- Pre-labeled wires with detailed pin-out diagram
- Compatible with 1,500+ HP applications
Product Notes
- Vehicle-specific – confirm compatibility with Haltech
- Requires NEXUS S2 or S3 ECU (sold separately)
- Professional installation recommended
California Proposition 65: Contains chemicals known to the State of California to cause cancer or reproductive harm.
Warranty: Limited lifetime against manufacturing defects to original purchaser.
Installation Notes
- Professional installation recommended
- Unplug factory ECU and plug in adapter harness
- Connect NEXUS S2/S3 to adapter harness
- Route and secure harness away from heat/moving parts
This Part Fits
| Application | ECU Upgrade |
|---|---|
| Popular Performance Platforms (Verify Compatibility) | NEXUS S2 / S3 |
Note: Vehicle-specific harness – contact Haltech for exact fitment list.
What's Included in the Purchase
- (1) NEXUS S2/S3 Plug-and-Play Adapter Harness
- Pin-Out Diagram & Installation Instructions
- Part Number: Haltech HT-186331
Why Choose Haltech?
- Over 30 years of motorsport ECU leadership
- Engineered for 1,500+ HP race & street applications
- Trusted in Formula Drift, V8 Supercars, and Dakar Rally
Frequently Asked Questions
-
Q: Does this fit my car?
A: Vehicle-specific – check Haltech compatibility chart -
Q: Cutting factory harness required?
A: No – true plug-and-play design -
Q: Includes ECU?
A: No – harness only, NEXUS S2/S3 sold separately
Shipping & Handling
- Method: UPS or Fed Ex Ground.
- Availability: Typically ships same day or next if in stock.
- Packaging: Protective retail box.
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