The 1990–1994 Nissan Pulsar GTi-R (N14 chassis) is fitted with the SR20DET, a 2.0 litre DOHC turbocharged inline-four managed by Nissan’s ECCS (Electronic Concentrated Control System) providing sequential multi-point fuel injection and electronic ignition control from a single ECM. The GTi-R mounts the SR20DET transversely for front-wheel drive, making its ECU connector wiring distinct from the longitudinal rear-wheel-drive SR20DET application used in the S13/S14/S15 Silvia and 180SX. The ECM is a 76-pin unit that interfaces with sensors including the mass air flow meter, throttle position sensor, coolant temperature sensor, and oxygen sensor, as well as controlling all four fuel injectors directly.
ECU - Electronic Control Unit Connector.
| Pin | name | Signal |
|---|---|---|
| 2 | Tachometer Signal | RPM |
| 16 | Mass Air Flow Sensor | Analog |
| 17 | Mass Air Flow Sensor Ground | Ground |
| 18 | Engine Coolant Temperature Sensor | Analog |
| 19 | O2 Sensor Signal | Analog |
| 20 | Throttle Position Sensor | Analog |
| 21 | Sensor Ground | Ground |
| 26 | Air Temperature Sensor | Analog |
| 32 | Vehicle Speed Sensor | Speed |
| 48 | Power Ground (Electronic Concentrated Control System) | Ground |
| 101 | Injector # 1 | Speed |
| 103 | Injector # 3 | Speed |
| 110 | Injector # 2 | Speed |
| 112 | Injector # 4 | Speed |
| 116 | Power Ground (Electronic Concentrated Control System) | Ground |
Notes
The GTi-R SR20DET ECU wiring is specific to the N14 transverse FWD platform and is not interchangeable with the S-chassis RWD SR20DET harness. The ECM connector is a 76-pin multi-pin header following Nissan’s standard ECCS layout for the B13/N14 generation. Only selected pins with known functions are listed above; remaining terminals are not publicly documented. The ECCS system supports self-diagnostic mode via the Nissan CONSULT serial interface.
Signals
- Tachometer Signal — engine speed output signal in RPM, used to drive the instrument cluster tachometer
- Mass Air Flow Sensor — analogue voltage signal from the hot-wire MAF sensor measuring intake air mass
- Mass Air Flow Sensor Ground — dedicated signal ground return for the MAF sensor
- Engine Coolant Temperature Sensor — analogue voltage signal from the NTC thermistor reporting coolant temperature to the ECM
- O2 Sensor Signal — analogue voltage from the exhaust oxygen sensor used for closed-loop fuelling correction
- Throttle Position Sensor — analogue voltage proportional to throttle plate angle; released approximately 0.5 V, fully depressed approximately 4.2 V
- Sensor Ground — common signal ground reference for analogue sensors
- Air Temperature Sensor — analogue voltage signal from the intake air temperature sensor
- Vehicle Speed Sensor — pulse signal proportional to road speed, used for speed-dependent ECM functions
- Power Ground (ECCS) — high-current chassis ground for the ECCS control unit (pins 48 and 116)
- Injector #1 / #2 / #3 / #4 — individual injector drive outputs; the ECM switches each injector to ground to deliver sequential fuel pulses