ECU - Electronic Control Unit Connector.
The 1996–1997 Honda Del Sol uses the same OBD2 ECM/PCM architecture as the contemporary EK-series Civic. Only the Del Sol Si continued into these model years, fitted with the D16Y5 or D16Y8 engine (VTEC). The ECM employs Honda’s PGM-FI multi-point fuel injection system and monitors sensors including MAP, throttle position, engine coolant temperature, intake air temperature, and primary and secondary oxygen sensors. A 16-pin Data Link Connector (DLC) provides OBD2 scan-tool access, and the VTEC solenoid valve and oil-pressure switch are managed through the A and C connector blocks respectively.
Connector A
| Pin | name | Signal |
|---|---|---|
| A8 | VTEC Solenoid Valve | Analog |
| A10 | Power Ground | Ground |
| A20 | Ignition Control Module | RPM |
| A23 | Power Ground | Ground |
Connector C
| Pin | name | Signal |
|---|---|---|
| C15 | VTEC Pressure Switch | Analog |
| C18 | Vehicle Speed Sensor | Speed |
Connector D
| Pin | name | Signal |
|---|---|---|
| D1 | Throttle Position Sensor | Analog |
| D2 | Engine Coolant Temperature Sensor | Analog |
| D3 | MAP Sensor | Analog 0.32V @ -13.9 PSI 4.84V @ 10.94 PSI |
| D5 | Brake Switch | Analog |
| D7 | Primary O2 Sensor | Analog |
| D8 | Intake Air Temperature Sensor | Analog |
| D14 | Secondary O2 Sensor | Analog |
Notes
- The ECM is located above the passenger footwell (kick panel area).
- Connector pins are numbered from the wire side of the connector with the locking tab at the top; do not probe from the pin side.
- To reset stored DTCs, disconnect the negative battery terminal for at least 30 seconds, or remove the ECM backup fuse. Clearing DTCs also erases idle learn data; an idle relearn procedure is required afterwards.
- The OBD2 16-pin DLC allows connection of a standard scan tool or Honda PGM Tester for live data and fault retrieval.
- Connector A pin A8 drives the VTEC solenoid valve; connector C pin C15 reads the VTEC oil-pressure switch confirming solenoid engagement.
Signals
- VTEC Solenoid Valve (A8) — ECM output that energises the VTEC solenoid to switch cam-profile at the programmed RPM/load threshold.
- Power Ground (A10, A23) — ECM power ground returns; both pins connect to chassis earth.
- Ignition Control Module (A20) — RPM signal path between the ECM and the ignition control module for timing control.
- VTEC Pressure Switch (C15) — Input confirming hydraulic oil pressure has risen sufficiently to engage the VTEC mechanism; monitored by the ECM.
- Vehicle Speed Sensor (C18) — Pulse signal from the vehicle speed sensor; used by the ECM for fuel-cut, idle control, and speed-related corrections.
- Throttle Position Sensor (D1) — Analogue voltage indicating throttle plate angle; used for load calculation and transient enrichment.
- Engine Coolant Temperature Sensor (D2) — Analogue signal from the ECT sensor; used to adjust fuel delivery, ignition timing, and idle speed during warm-up.
- MAP Sensor (D3) — Manifold absolute pressure; ranges approximately 0.32 V at −13.9 PSI to 4.84 V at 10.94 PSI; primary load input for the PGM-FI system.
- Brake Switch (D5) — Input indicating brake pedal application; used for torque converter lock-up control and fuel-cut logic.
- Primary O2 Sensor (D7) — Upstream heated oxygen sensor signal used for closed-loop air/fuel ratio correction.
- Intake Air Temperature Sensor (D8) — Analogue signal used to correct fuel delivery for inlet air density.
- Secondary O2 Sensor (D14) — Downstream oxygen sensor signal used for catalytic converter efficiency monitoring.