RX3 ECU signals
This page is under development. It documents the various signals lines going to and coming from the Engine Control Unit (ECU) of the RX3. It's Dephi MT05 system.
The table and diagram are generic, not specific for the RX3. The Delphi MT05 can be used with both single and twin cylinder engines and has signals for two cylinders. On the RX3 only one set is used.
Use any of this data at your own risk. Accuracy is not guaranteed.
| Abbreviation | Description |
| VBAT | Battery |
| IGN | Switched Ignition |
| 5VREF | 5V Reference Voltage |
| 5VRTN | 5V Return (S Ground) |
| GND | Power Ground |
| COIL A | COIL A |
| COIL B | COIL B |
| INJ A | INJ A |
| INJ B | INJ B |
| IACAHI | Stepper Motor AHi |
| IACALO | Stepper Motor ALo |
| IACBHI | Stepper Motor BHi |
| IACBLO | Stepper Motor BLo |
| PUMP/FPR | Fuel Pump (or Fuel Pump Relay) |
| PWM IDLE | PWM Idle Valve |
| O2HTR | O2 heater |
| MIL | MIL Malfunction Indicator Light |
| MAGCUT | Magneto Cut Relay |
| TACHO | Tacho Rotational speed output |
| NEUTRAL SW | Neutral Switch |
| ROLL SW | Spare/Roll-over switch |
| DIAG SW | Diagnostic Switch |
| O2LO | O2 LO |
| K-LINE | K-LINE |
| IMMOB-IN | IMMOB-IN |
| IMMOB-OUT | IMMOB-OUT |
| CANHI | CANHI |
| CANLO | CANLO |
| O2HI/CO | Front O2 Hi/CO Adjust |
| ETS | Coolant/Engine Temp |
| IAT | Inlet Air Temp Sensor (IAT) |
| MAP | MAP(internal) Intake air Compression |
| TPS | Throttle Position Sensor (TPS)/Desired Engine Speed |
| CRK HI | Crank VR Hi |
| CRK LO | Crank VR Lo |
| VSS | VSS Vehicle Speed |
Below is the Delphi description of the pinouts
On the RX3, J1 has only the following pins connected (despite what the wiring diagram shows) - 1, 3, 6, 7, 8, 9, 11, 12, 13, 17 and 18
