FAQ : HONDA Civic OBD0 EF ECU PINOUTS

For fans of the 1988-1991 Honda Civic / CRX and EF, as well as the 1990-1991 Acura Integra, we are adding another chapter to our ECU pinouts library. Our DPFI to MPFI OBD0 pinout will help you get the job you are looking for done. These Honda Civic OBD0 EF ECU Pinouts will list all the ecu pins and values you need for any engine swap or conversion.

For a list of what fits what in our Honda series, check here and part 2 here.

Pinout ’88 HF/Si ’90-1 DX (Std.) ’90-1 HF/Si

A1 No.1 INJ Aux INJ w/A3 No.1 INJ

A2 GRD w/A4 to Main Relay GRD w/A4 to Main Relay GRD w/A4 to Main Relay

A3 No.2 INJ Aux INJ w/A1 No.2 INJ

A4 GRD w/A2 to Main Relay GRD w/A2 to Main Relay GRD w/A2 to Main Relay

A5 No.3 INJ Main INJ w/A7 No.3 INJ

A6 Purge Cut-Off Solenoid Valve Purge Cut-Off Solenoid Valve Purge Cut-Off Solenoid Valve (HF Only)

A7 No.4 INJ Main INJ w/A5 No.4 INJ

A8 Lock-up Control Solenoid Valve Lock-up Control Solenoid Valve Lock-up Control Solenoid Valve

A9 – – –

A10 – EGR Valve (CA A/T Only) EGR Valve (HF Only)

A11 EACV w/A17 EACV w/A17 EACV w/A17

A12 Main Relay w/A14 Main Relay w/A14 Main Relay w/A14

A13 Main Relay w/A15 Main Relay w/A15 Main Relay w/A15

A14 Main Relay w/A12 Main Relay w/A12 Main Relay w/A12

A15 Main Relay w/A13 Main Relay w/A13 Main Relay w/A13

A16 GRD w/A18 GRD w/A18 GRD w/A18

A17 EACV w/A11 – –

A18 GRD w/A16 GRD w/A16 GRD w/A16

B1 Hazard Fuse w/Brake Switch Hazard Fuse w/Brake Switch –

B2 Tandem Valve Control Solenoid Valve Tandem Valve Control Solenoid Valve –

B3 A/C Clutch Relay A/C Clutch Relay Fast Idle Valve

B4 Radiator Fan Relay Radiator Fan Relay Radiator Fan Relay

B5 Alternator Alternator Alternator

B6 Check Engine Light Check Engine Light Check Engine Light

B7 Shift Position Sensor (A/T Only) Shift Position Sensor (A/T Only) A/C Switch w/B8

B8 A/C Switch A/C Switch A/C Switch w/B7

B9 – – –

B10 – – Crank Angle Sensor

B11 Shift Position Sensor (AT Only) Shift Position Sensor (AT Only) Clutch Switch (HF Only)

B12 – – Crank Angle Sensor

B13 No.2 Fuse (10A) No.2 Fuse (10A) No.2 Fuse (10A)

B14 Alternator Alternator Alternator

’89-92 EF8/9 SiR

No.1 INJ

GRD w/A4 to Main Relay

No.2 INJ

GRD w/A2 to Main Relay

No.3 INJ

Purge Cut-Off Solenoid Valve

No.4 INJ

Spool (VTEC) Solenoid Valve

• Pressure Regulator Cut-Off Solenoid Valve
• EACV
• Main Relay w/A14
• Main Relay w/A15
• Main Relay w/A12
• Main Relay w/A13
• GRD w/A18

GRD w/A16

Hazard Fuse w/Brake Switch

• B15 Igniter Unit w/B17 Igniter Unit w/B17 Igniter Unit w/B17
• B16 Speed Sensor Speed Sensor Speed Sensor
• B17 Igniter Unit w/B15 Igniter Unit w/B15 Igniter Unit w/B15
• B18 – – –
• B19 ELD ELD ELD
• B20 Ign. Timing Adj. Connector Ign. Timing Adj. Connector Ign. Timing Adj. Connector
• C1 Crank Angle Sensor Crank Angle Sensor Cylinder Position Sensor
• C2 Crank Angle Sensor Crank Angle Sensor Cylinder Position Sensor
• C3 TDC Sensor TDC Sensor TDC Sensor
• C4 TDC Sensor TDC Sensor TDC Sensor
• C5 TA Sensor TA Sensor TA Sensor
• C6 TW Sensor TW Sensor TW Sensor
• C7 Throttle Angle Sensor Throttle Angle Sensor Throttle Angle Sensor
• C8 – EGR Valve Lift Sensor (CA A/T Only) –
• C9 PA Sensor PA Sensor PA Sensor
• C10 Brake Switch Brake Switch Brake and Reverse Light Switch (HF Only)
• C11 MAP Sensor MAP Sensor MAP Sensor
• C12 PA Sensor PA Sensor Throttle Angle Sensor
• C13 PA Sensor PA Sensor Throttle Angle Sensor
• C14 MAP Sensor MAP Sensor MAP Sensor
• C15 MAP Sensor MAP Sensor MAP Sensor
• C16 O2 Sensor A O2 Sensor A O2 Sensor A

1. Igniter Unit w/B17
2. Speed Sensor (Electrical)
3. Igniter Unit w/B15

1. #4 Injector
2. EACV (Coil)
3. Main Relay
4. Main Relay/Injector Resistor Box
5. Main Relay
6. Main Relay/Injector Resistor Box
7. Ground
8. Ground
9. Function
10. Hazard Fuse
11. Fast Idle Control Solenoid Valve
12. A/C Clutch Relay
13. Radiator Fan Relay
14. Alternator
15. Check Engine Warning Light
16. A/C Switch
17. Crank Angle Sensor
18. Crank Angle Sensor

• B13 Blue White Main Relay Blue White
• B14 Blue 2 To Yellow, To Alternator Blue 2
• B15 White 1 Ignitor Unit White 1
• B16 Yellow/Red Speed Sensor Yellow/Red
• B17 White 2 Ignitor Unit White 2
• B18
• B19 Green/Red Electric Load Detector Green/Red
• B20 Brown Ignition Timing Adjusting Connector Brown
• Pin# Wire Color Function Wire Color
• C1 Orange Crank Angle Sensor Blue/Green
• C2 White 4 Crank Angle Sensor Blue/Yellow
• C3 Orange/Blue TDC Sensor Orange/Blue
• C4 White/Blue TDC Sensor White/Blue
• C5 Red/Yellow TA Sensor Red/Yellow
• C6 Red/White 1 TW Sensor Red/White 1
• C7 Red/Blue Throttle (Position) Angle Sensor (TPS) Red/Blue
• C8 Yellow EGR Lift Valve Sensor
• C9 Red/White 2 PA Sensor Red/White 2
• C10 Green/White 3 Brake Switch Green/White 3
• C11 White 1 MAP Sensor White 1
• C12 Green/White 2 EGR Lift Valve Sensor/Pa Sensor/Ignition Timing Adjusting Connector/TA Sensor/TPS Sensor/TW Sensor Green White 2
• C13 Yellow/White EGR Lift Valve Sensor/Pa Sensor/TPS Sensor Yellow/White
• C14 Green/White 1 MAP Sensor Green/White 1
• C15 Yellow/Red MAP Sensor Yellow/Red
• C16 White 3 O2 Sensor White 3

That does it for our HONDA Civic OBD0 EF ECU PINOUTS article, please leave us any comments or questions below