The Nissan Skyline R33 (chassis codes ECR33 for the GTS-T and BCNR33 for the GT-R) was produced from 1993 to 1998 and fitted the RB25DET, a 2.5 litre twin-cam turbocharged inline-six engine managed by Nissan’s ECCS (Electronic Concentrated Control System). The ECU (Engine Control Unit) provides sequential multi-point fuel injection and electronic ignition timing control, interfacing with sensors and actuators across the engine bay via a multi-pin connector harness. The R33 GTS-T ECU employs an expanded terminal layout with pin numbers reaching into the 100-series for injector drive signals, reflecting the integrated engine and emissions control architecture documented in the Nissan R33 engine service manual.
ECU - Electronic Control Unit Connector.
| Pin | name | Signal |
|---|---|---|
| 7 | Tachometer Signal | Speed |
| 10 | Power Ground (Engine Control Module) | Ground |
| 26 | Mass Air Flow Sensor Ground | Ground |
| 27 | Mass Air Flow Sensor | Analog |
| 28 | Engine Coolant Temperature Sensor | Analog |
| 29 | O2 Sensor Signal | Analog |
| 30 | Sensor Ground | Ground |
| 38 | Throttle Position Sensor | Analog |
| 53 | Vehicle Speed Sensor | Speed |
| 55 | O2 Sensor Signal | Analog |
| 101 | Injector # 1 | Speed |
| 103 | Injector # 3 | Speed |
| 105 | Injector # 2 | Speed |
| 110 | Injector # 5 | Speed |
| 112 | Injector # 4 | Speed |
| 114 | Injector # 6 | Speed |
Notes
The R33 GTS-T (ECR33) uses the RB25DET engine; the R33 GT-R (BCNR33) uses the RB26DETT with a separate and incompatible ECU connector layout — do not interchange pinout references between the two variants. The ECU connector harness follows Nissan’s ECCS multi-pin arrangement; pin numbers in the 100-series are injector drive outputs, while lower-numbered pins carry sensor inputs and ground references. The CONSULT serial diagnostic interface is accessible via a dedicated 14-pin data link connector on the dashboard, separate from the ECU harness. Injector signal direction is listed as “Speed” in the table, reflecting the original source column heading.
Signals
- Tachometer Signal — engine speed output signal to the instrument cluster tachometer
- Power Ground (Engine Control Module) — main chassis/engine ground for the ECM
- Mass Air Flow Sensor Ground — dedicated signal ground for the MAF sensor circuit
- Mass Air Flow Sensor — analogue voltage input from the hot-wire mass air flow sensor; used to calculate fuel injection quantity
- Engine Coolant Temperature Sensor — analogue voltage input from the coolant temperature thermistor; used for cold-start enrichment and ignition timing correction
- O2 Sensor Signal (pin 29) — analogue voltage input from the upstream (pre-catalyst) oxygen sensor for closed-loop fuelling
- Sensor Ground — common signal ground reference for analogue sensor inputs
- Throttle Position Sensor — analogue voltage input indicating throttle plate angle; used for load calculation and acceleration enrichment
- Vehicle Speed Sensor — pulse signal indicating road speed; used for idle control and fuel cut strategies
- O2 Sensor Signal (pin 55) — analogue voltage input; function not publicly documented for this variant (may be a second O2 sensor or duplicate reference)
- Injector #1 – #6 — sequential injector drive outputs (low-side switching); pins 101, 103, 105, 110, 112, and 114 drive cylinders 1 through 6 respectively