Nexus T2 and T1 ECU
Nexus T2 and T1 ECU
ECU overview
The Nexus T2/T1 ECUs stand at the forefront of engine management systems, featuring cutting edge technology and innovative features.
Designed for the next generation of automotive enthusiasts and professionals, these state of the art ECUs seamlessly combine powerful engine control with a range of additional functionalities, making them versatile and comprehensive solutions for everything from everyday driving to high performance racing.
The Nexus T2/T1 ECUs are fully compatible with a myriad of Haltech devices, streamlining the configuration of engine parameters and additional functionalities, all programmable using a single piece of software.
Experience high-speed USB and wireless connectivity, allowing for seamless communication between the ECU and your tuning device. The Nexus T2/T1 ECUs are revolutionary engine management systems that transcend conventional boundaries, offering a comprehensive solution for performance tuning and control. With their advanced features, user-friendly interface, and seamless connectivity, they redefine the standard for engine management systems in the automotive industry.
Optional accessories (sold separately)
• HT-030009 - AMP 34-pin Key 1 plug and pins set• HT-181200 - Nexus T2/T1 Basic universal wiring harness 2.5m (8’)• HT-181201 - Nexus T2/T1 Premium universal wiring harness 2.5m (8’)• HT-159976 - WB1 Bosch LSU 4.9 Single Channel CAN O2 Wideband Controller Kit• HT-159986 - WB2 Bosch LSU 4.9 Dual Channel CAN O2 Wideband Controller Kit
Nexus T2 and T1 ECU dimensions
Nexus T2 and T1 ECU LED behavior
Nexus T2 and T1 ECU specifications
Nexus Software Programmer (NSP)
Installing NSP
Haltech NSP (Nexus Software Programmer) is the software used for tuning and programming the Nexus Rebel JZ ECU. Follow these steps to install the Haltech NSP software:
1. Download the NSP installer - Go to the Haltech website (www.haltech.com), navigate to the ‘Downloads’ section, and click on the download link.
2. Run the installer file - Once the download is complete, locate the downloaded file (usually in the ‘Downloads’ folder of your computer) and double-click on the file to run the Nexus Software Setup Wizard.
3. Launch Haltech NSP - Once the installation is complete, you can launch the Haltech NSP software from the Windows ‘Start’ menu or using the desktop shortcut that was created.
Going online with the ECU
With the NSP software open, connect the supplied Haltech USB cable between your laptop and the USB-C port on the front of the Nexus T2/T1 ECU.
The USB connection allows the NSP software to automatically recognize the ECU and activate it in low-power mode. This enables you to either upload a basemap or create a new one before installing the ECU into the vehicle. In low-power mode, the ECU’s inputs and outputs are disabled, allowing you to safely configure your vehicle setup before installation and full power activation.
Setting up Wireless communications
Wireless communication is another method for connecting the Nexus T2/T1 ECU to your laptop or mobile device (see Haltech Connect App), serving as an alternative to a USB connection once the Wireless module is enabled.
To set up your Wireless connection follow these steps:
1. Open NSP and connect your Nexus T2/T1 ECU using the provided USB-C cable.
2. Click on ‘Connections’ in the navigation tree and enable the Wireless module.
3. Under ‘Connections’, select ‘Wireless’ to set up your SSID and password.
Note that your SSID must be at least 1 character long, and your password at least 8 characters. Click ‘Apply’.
4. Power up the ECU using main power (ignition switch on), then go to your computer’s Network settings. Connect to your Nexus T2/T1 ECU by selecting your chosen SSID and entering your password.
NOTE: The Wireless antenna is internal on the Nexus T2/T1 ECU. The unit must be powered by the main power source for Wireless communication.
Up to two computers can connect to the ECU via Wireless, and one via USB-C, at any given time.
When the Wireless module is disabled, it is completely inactive and held in an OFF state.
Haltech Connect App
The Haltech Connect App enables you to connect wirelessly to and interact with your Haltech Nexus T2/T1 ECU via your smartphone or tablet. View real-time data from the ECU, set up basic gauges, clear DTCs, assign wiring, and adjust select parameters. Available for free on Google Play (Android) and the Apple App Store (iOS).
Nexus T2 and T1 ECU wiring
Power and Ground Pins
The Nexus T2 or Nexus T1 ECU power (A26) and ground (A10) pins must be wired correctly to ensure reliable and effective operation. The ECU ground pin must be wired directly to the battery negative terminal. The power supply pin must be fused and switched through an Engine Control Relay (ECR) to provide a stable and protected power supply. The ECR must be wired so that the relay receives a switched 12V signal from the ignition switch, and that this signal remains active when the ignition key is in both the ON and START positions. This ensures the ECU remains powered during ignition and engine cranking, preventing start‑up issues that could place unnecessary strain on engine components. The wiring diagram provided below illustrates this configuration in detail.
The relay shown in the wiring diagram is a HT-030205 micro relay using the following internal schematic:
If you are using a different relay, ensure that it is wired according to that relay’s specific switching schematic.
Crank (Trigger) and Cam (Home) Inputs
The crank and cam position sensors are necessary for providing the ECU with vital information to determine engine speed and position at any given moment. Typically, two sensors are required – one for cam position and one for crank position. However, many engines may only have a cam position sensor capable of supplying sufficient information for the ECU to effectively manage engine operation. Vehicles equipped solely with a crank position sensor lack the capability to differentiate between compression and exhaust strokes, making them unsuitable for sequential fire applications. In such cases, it may be necessary to add a cam position sensor. It is recommended to use four-core or twin-core shielded cable for crank and cam position sensors. Shields must be terminated to battery ground atone end only.
Specs:
• -10V to +10V input• Selectable 1k2 or 440R pull-up to 5V• Selectable ground reference (full differential standard mode)• -75 to +75V indefinite withstand• 48kHz max signal frequency
There are two common types of crank/cam sensor signals:
• Hall effect/optical signal (0-5V digital square wave signal)This type of sensor sends out a digital square wave signal.Hall effect sensors typically have three wires: a power supply, sensor ground, and a signal output wire.The power supply can be drawn from the ECU’s +12V supply pin (A26) or the +5V pin (A9) as required by the sensor used.The internal pull-up will typically need to be enabled in the software settings for Hall effect/optical sensors.
• Reluctor signal (analog style signal)This type of sensor generates a sine wave signal and typically uses two wires: signal positive (+) and signal negative (-).Reluctor sensors do not require external power, as they are passive sensors and can generate their voltage signal by sensing a moving tooth or trigger.It is important to disable the internal pullup in the NSP settings for reluctor sensors.
Injector Outputs
All injectors should be directly wired to the ECU’s corresponding cylinder output pins. During an injection event, the ECU grounds the output pin, prompting the injector to open and flow fuel for a specified duration.
It is essential to wire all injectors to a common +12V supply switched by a relay.
When not used for injection, these pins can be utilized as generic Digital Pulsed Outputs (DPO), capable of switching 2A to ground.
Specs:
• Number of channels - Nexus T2: 6 | Nexus T1: 4• Current controlled output• 8A Peak, 2A Hold• 0 to 55V voltage feedbackUnused injector outputs can also be used as:• Generic switched or PWM outputs (2A)• Low speed digital switch inputs (0-12V)
Ignition Outputs
The ignition outputs generate a signal between 12V and ground to control the charging and firing of an ignition coil. Ignition outputs can be connected directly to ignition coils only if the coils are equipped with internal ignitors. Ignition coils without internal ignitors draw large amounts of current and, as such, must use an external ignitor module to be safely triggered by the ECU.
Connecting directly to ignition coils without internal ignitors will result in damage to the ECU.
Specs:
• Number of channels - Nexus T2: 6 | Nexus T1: 4• Software selectable global 12V or 5V pull-up• Software selectable individual 270R pull-up• 10kHz switching speed• Automatic overtemp, overcurrent, flybackprotection• 0 to 27V voltage feedbackUnused ignition outputs can also be used as:• Generic DPO (3A sink) or PWM outputs• Low speed digital switch inputs (0-12V)
WARNING
Connecting the ECU to an ignition module before setting the ignition firing edge correctly may damage the module and coils.
Therefore, it is advised to disconnect the module or disable the power to the ignition system until the unit has been set up and configured.
Digital Pulsed Outputs (DPO)
Digital Pulsed Outputs (DPO) are designed to ground-switch devices or to provide frequency based control or pulse width modulation as needed.
Each DPO channel has a maximum sink current of 3A and directly drive low current devices such as boost control solenoids, VVT oil control valves, idle air control valves, etc.
Devices that draw more current can still be controlled by DPOs by wiring a relay in between to drive high current devices such as fuel pumps or thermofans.
Unused DPOs can also function as low-speed digital switch inputs (0-12V).
Specs:
• Number of channels: 5• Low side drive (3A max current)• Software selectable 4k7 pullup to +12V or +5V• Overcurrent and flyback protection• Over temperature protection• 10kHz switching speed• 0 to 27V feedback
Haltech CAN System
The Nexus T2/T1 ECU features CAN connectivity through the main ECU connector.
This single CAN channel can be used with a wide range of Haltech CAN devices such as Wideband O2 modules, dash displays, CAN keypads, and the Nexus IO16 Input and Output Expander, via a Haltech CAN Hub.
Analog Voltage Inputs (AVI)
Analog Voltage Inputs are inputs to the Nexus T2/T1 ECU that accept variable voltage signals ranging from 0V to 5V, such as signals from pressure, temperature, and position sensors.
These inputs can also accept switched inputs that change between two different voltage levels. The On Voltage and Off Voltage set in NSP define the thresholds between the On and Off states.
Specs:
• Number of channels: 5• 0 to 5V analog inputs• 1000 samples per second• Selectable 1k pull-up to 5V• -10 to +30V indefinite withstand• 1.5kHz signal frequency max
Common examples of switched inputs include the A/C Request switch or a Launch Control Enable switch. AVIs feature a software-selectable 1K pull-up resistor to 5V, which can be enabled or disabled within the setup page.
Pull-up resistors are generally enabled for temperature-related sensors and switched-to-ground inputs, and disabled for inputs with an external +5V supply, such as a MAP sensor or throttle position sensor.
Synchronized Pulsed Inputs (SPI)
Synchronized Pulsed Inputs are capable of measuring the position, duty cycle, frequency, or state of a signal. These inputs are suitable for sensors such as a cam sensor for variable valve timing, flex fuel composition sensors, and vehicle speed sensors. Synchronized Pulsed Inputs are compatible with both digital (hall effect or optical) and analog (reluctor) based sensors. They have a maximum input voltage rating of 25V and can measure up to a maximum frequency of 22.5kHz.
Specs:
• Number of channels: 2 (SPI 1 + Knock/SPI 2)• -10 to +10V digital input• 0 to 5V analog input• Selectable 1k pull-up to 5V• -15 to +30V indefinite withstand• 22.5kHz signal frequency max
Knock Input
A knock sensor detects engine knock and sends a voltage signal to the Nexus T2/T1 ECU through the knock input. The ECU utilizes the knock sensor signal to adjust ignition timing if knocking is detected. Knock detection can be achieved by installing a compatible piezoelectric knock sensor mounted to the engine block. It is recommended to use twincore shielded cable for knock sensors, with shields terminated to battery ground at one end only.