Haltech Nexus S3 ECU & Lexus SC300 | Toyota Supra 2JZ-GE 1992-1997 Plug 'n' Play Adapter Harness Kit - A340E Automatic (HT-651372)

This Tuned By Shawn plug-and-play kit (HT-651372) pairs the Haltech Nexus S3 ECU with the matching Boomslang adapter harness (BF29214) for the 1992-1997 Lexus SC300 and 1993-1997 Toyota Supra 2JZ-GE (non-VVT-i 2JZ-GE engine, A340E automatic) with an automatic transmission. The harness plugs into the factory engine harness where the stock ECU connects, so the Nexus S3 takes over full standalone engine management with no cutting, splicing or repinning.

Vehicle Fitment

• 1992-1997 Lexus SC300 (automatic transmission)
• 1993-1997 Toyota Supra 2JZ-GE (automatic transmission)

Boomslang part number: BF29214. Confirm your model year, engine and transmission before ordering. Similar-looking vehicles often use a different factory ECU connector or pinout and need a different harness.

ECU Included

This kit includes the Haltech Nexus S3 ECU, and the Boomslang harness is built for its connectors.

Features

• Vehicle-specific plug-and-play fitment for the 1992-1997 Lexus SC300 and 1993-1997 Toyota Supra 2JZ-GE
• Plugs into the factory engine harness with no cutting, splicing or repinning
• Factory harness is left untouched, so the install is fully reversible
• OEM-style connectors and correct wire gauge throughout
• Built in the USA by Boomslang
• Complete kit: Haltech Nexus S3 ECU plus the matching harness in one order

What's in the Box

• 1x Boomslang plug-and-play wiring harness (BF29214) for the 1992-1997 Lexus SC300 and 1993-1997 Toyota Supra 2JZ-GE
• Haltech Nexus S3 ECU
• Haltech air temperature sensor, small thread (M14 x 1.5)

Transmission

The automatic cars run the A340E, Aisin's electronically controlled four-speed used across Toyota's longitudinal rear-drive platforms. The automatic chassis uses a different engine-bay connector layout than the manual, which is why this harness carries its own part number. Check the code stamped on the transmission ID plate before ordering — if the car is a manual, you want the manual-transmission harness instead.

Frequently Asked Questions

Does this kit require cutting the factory wiring?

No. The Boomslang harness plugs into the factory engine harness connectors, so the stock wiring stays intact and the vehicle can be returned to stock.

Which vehicles does HT-651372 fit?

The 1992-1997 Lexus SC300 and 1993-1997 Toyota Supra 2JZ-GE with an automatic transmission.

Does it need a tune after installation?

Yes. A Haltech standalone ECU must be calibrated for your engine and modifications before the vehicle is driven. Tuned By Shawn offers remote and in-person Haltech tuning. Email service@tunedbyshawn.com with any fitment questions before you order.

For off-road and competition use only. Not legal for use on pollution-controlled motor vehicles.