ECU spec · Haltech

Haltech Nexus T2 pinout and specs

Haltech Nexus T2 is a 34-pin wire-in Haltech ECU on 1 connector: A (34 pins).

It has 6 injector outputs and 6 ignition outputs. The injector drivers are peak-and-hold, so low-impedance injectors run without a resistor pack. The ignition outputs are logic-level. Smart coils plug straight in; dumb coils need an igniter in between.

There are 2 dedicated trigger inputs, each happy with a VR or a Hall sensor. One knock input covers an inline engine. Wideband control needs an external controller, usually over CAN. The MAP sensor is built in.

It does not drive an electronic throttle, so plan on a cable throttle. One CAN bus handles dashes, PDMs and expansion. The maker rates the 5V sensor supply at 200 mA in total.

Spec sheet

ConnectorsA (34)34 pins in this profile
Injector outputs6peak-and-hold (low-impedance capable)
Ignition outputs6logic-level: smart coils, or an igniter for dumb coils
Dedicated trigger inputs2VR or Hall
Knock inputs1
Onboard wideband controllers0
Onboard MAP sensorYes
CAN buses1
Drive-by-wireNo
High-side outputs0
Half-bridge outputs0
5V sensor supply1 pin200 mA stated by the maker

Worth knowing

  • The knock input shares pin A13 with SPI 2: one or the other.

Which builds it suits

Of the 58 swap presets in the planner, 0 fit as they are and 13 fit with add-ons; 45 do not fit at all. The add-on it asks for most often is the Haltech WB1 (single-channel CAN wideband). Where it falls short, it is usually not enough injector output (low-side). The planner fills anything a preset leaves open with its ordinary defaults, so your own build may land differently.

The Toyota 2JZ-GE distributor (NA, early) needs Haltech WB1 (single-channel CAN wideband) and Haltech HPI8 High Power Igniter (8-channel). The Mazda Rotary 13B-REW (FD RX-7) needs Haltech PD16 (Power Distribution Module) and Haltech WB1 (single-channel CAN wideband). It can't run the GM LT1 (Gen5 6.2 alum): not enough injector output (low-side). It can't run the Nissan RB25DET non-Neo S1 (R33, dumb coils): not enough knock inputs. It can't run the Mazda Rotary 13B-MSP Renesis (RX-8 manual, 6-injector): not enough drive-by-wire throttle motor (h-bridge).

Fits with add-ons 13
Does not fit 45

Plan a build around the Haltech Nexus T2

Pin table

Connector A carries 6 injector outputs, 6 ignition outputs and 2 trigger inputs.

Show all 34 pins
PinFunction
A 1DPO 2
A 2AVI 1
A 3Ignition 1
A 4Ignition 2
A 5Ignition 3
A 6Ignition 4
A 7Ignition 5 (Nexus T2 only)
A 8Ignition 6 (Nexus T2 only)
A 9+5V sensor supply
A 10Power ground
A 11Sensor ground
A 12SPI 1
A 13Knock / SPI 2
A 14AVI 2
A 15AVI 3
A 16CAN High
A 17CAN Low
A 18DPO 1
A 19Injector 1
A 20Injector 2
A 21Injector 3
A 22Injector 4
A 23DPO 3
A 24DPO 5
A 25DPO 4
A 26+12V ECU power supply
A 27Injector 5 (Nexus T2 only)
A 28Injector 6 (Nexus T2 only)
A 29AVI 4
A 30AVI 5
A 31Trigger +
A 32Home +
A 33Trigger -
A 34Home -

Other Haltech ECUs

The closest Haltech unit is the Haltech Elite 750. Against it, this one has 1 knock input (the Elite 750 has 0).

Source: Haltech documentation for the Nexus T2

Always verify against the manufacturer's manual and your tuner before wiring.