OBD2A HONDA ECU PINOUTS - OEM - 1996-1998

1996-1998 Civic | 1996-1999 Integra

1 2 3 4 5 6 / 8 9 10 11
12 13 14 15 16 17 18 19 20 / 22 23 24
25 26 27 28 29 / / /
*D16Y7 harnesses require 3-wire IACV conversion to 2-wire at the ECU and the IACV.
OBD2A ECU A (32 Pin) C132
Pin Wire Color Terminal Name Description Test
1 YEL INJ4 Injector 4 Engine running: (-) Pulses
2 BLU INJ3 Injector 3 Engine running: (-) Pulses
3 RED INJ2 Injector 2 Engine running: (-) Pulses
4 BRN INJ1 Injector 1 Engine running: (-) Pulses
5 GRN/RED SO2SHTC Secondary O2 Sensor Heater Control Ignition On: 12V
6 ORN/BLK PO2SHTC Primary O2 Sensor Heater Control Ignition On: 12V
8 GRN/YEL VTS VTEC SOLENOID VALVE Low RPM: 0V, High RPM: 12V
9 BRN/BLK LG1 Logic Ground 1 Chassis ground
10 BLK PG1 Power Ground 1 Less than 1V at all times
11 YEL/BLK IGP1 Ignition Power 1 Ignition On: 12V
12 BLK/BLU IACV Idle Air Control Valve Idle: 6 - 10V
13* ORN IACV - (D16Y7, automatic) 3-Wire IACV Negative De-pin and leave hanging
14* YEL/BLK IACV + (D16Y7, automatic) 3-Wire IACV Positive De-pin and move to A12
15 RED PCS Purge Control Solenoid Coolant Temp > 154F: 12V when activated
16 GRN/BLU FLR Fuel Relay (Main Relay) 0V when activated, 12V resting
17 BLK/RED ACC Air Conditioning Clutch AC On: 0V, AC Off: 12V
18 GRN/ORN MIL Malfunction Indicator Light On: 0V, Off: 12V
19 WHT/GRN ALT C Alternator Control 12 - 0V
20 YEL/GRN ICM Ignition Control Module Key (III): 12V, Engine running: ~10V
22 BRN/BLK LG2 Logic Ground 2 Chassis ground
23 BLK PG2 Power Ground 2 Less than 1V at all times
24 YEL/BLK IGP2 Ignition Power Ground 2 Key (III): 12V
25 WHT/BLK VREF Voltage Reference Key (III): 5V
26 PNK/BLU IAB SOL Intake Air Bypass Solenoid (GSR B18C1) Below 5750RPM: 12V
27 GRN FANC Radiator Fan Switch Fan Running: 0V
28 BLU 2WBS EVAP Bypass Solenoid Key (III): 12V
29 LT GRN VSV EVAP Vent Shut Valve Key (III): 12V

 

1 2 3 4 5 6 7 8 9 10
11 12 13 14 15 16 17 18 19 / 21 /
/ / / / 27 28 29 / /
OBD2A ECU C (31 Pin) C134
Pin Wire Color Terminal Name Description Test
1 BLU/RED CKF P Crank Fluctuation (Power) Engine running: Pulses
2 BLU CKP P Crank Position (Power) Engine running: Pulses
3 GRN TDC P Top Dead Center (Power) Engine running: Pulses
4 YEL CYP P Cylinder Position (Power) Engine running: Pulses
5 BLU/RED AC Switch (ACS) Detects AC switch AC switch On: 0V, AC Switch Off: 12V
6 BLU/WHT Starter Switch Signal (STS) Detects starting Engine cranking: 12V
7 BRN/WHT Service Check Signal (SCS) Enables Diagnostic mode Jumpered: 0V, Not jumpered: 5V
8 GRN/WHT K-Line OBD2 Scan Signal Ignition on: 5V
9 YEL A/T TCM feedback signal Automatic Transmission Idle: 5V During Shifting: momentary 0V
10 WHT/BLU VBU Voltage Backup ECU Power source 12V
11 WHT/RED CKF M Crank Fluctuation (Ground)
12 BLU/YEL CKP M Crank Position (Ground)
13 WHT/BLU TDC M Top Dead Center (Ground)
14 WHT CYP M Cylinder Position (Ground)
15 BLU/BLK VTP SW (USDM) VTEC Pressure Switch VTEC ON: 12V
16 GRN PSP SW Power Steering Pressure Switch When steering: 12V
17 WHT/RED ALT F Alternator FR Signal Engine running: voltage dependent on electrical load
18 ORN VSS Vehicle Speed Sensor Engine running, wheels spinning: 0 - 5V cycles
19 BLU AT CHK Automatic Data Line Ignition: pulses
21 LT GRN BARO OUT Barometric Sensor Output ~3V
23 BLK IP+ (HX) Wideband O2
24 RED IP-/VS- (HX) Wideband O2
25 WHT VS+ (HX) Wideband O2
27 GRY AFSB Automatic Signal B Idle: 5V, During shifting: momentary 0V
28 GRN/BLU AFSA Automatic Signal A Idle: 5V, During shifting: momentary 0V
29 LT GRN/BLK AT PPN Automatic Gear Position Switch Park or Neutral: 0V, All others: 12V

 

1 2 3 4 5
6 7 8 / 10 11 12
13 14 15 16
OBD2A ECU D (16 Pin) C135
Pin Wire Color Terminal Name Description Test
1 RED/BLK TPS Throttle Position Sensor Fully Open: 4.5V, Closed: .5V
2 RED/WHT ECT Engine Coolant Temp .1 - 4.8V
3 WHT/YEL MAP Manifold Absolute Pressure 3V, Idle ~1V
4 YEL/WHT VCC1 Sensor Voltage 1 (MAP) 5V
5 GRN/WHT BKSW Brake Switch signal Brake pressed: 12V
6 RED/BLU KS Knock Sensor (GSR, Type R) pulses
7 WHT PHO2S Primary Heated Oxygen Sensor signal Full throttle, operating temperature > .6V, Decel > .4V
8 RED/YEL IAT Intake Air Temperature .1 - 4.8V
10 YEL/BLU VCC2 Sensor Voltage 2 5V
11 GRN/BLU SG2 Sensor Ground 2 Chassis ground
12 GRN/WHT SG1 Sensor Ground 1 Chassis ground
13 ORN/BLU SHO2S GND Secondary Heated O2 sensor ground Chassis ground
14 BLU/RED SHO2S Secondary Heated O2 sensor signal Full throttle, operating temp: .6V, Deceleration: .4V
15 LT GRN PTANK Fuel Tank Pressure sensor Gas Cap Off: 2.5V
16 GRN/RED ELD Electric Load Detector Parking Lights On, Idle: 2.5 - 3.5V, Headlights On: 1.5 - 2.5V

 

O2 Sensors

Civic HX "Wideband" "5 Wire O2" or "7 Wire O2" Sensor
BLK/WHT PO2SHTC
A6
 BLK
G101
 GRN/BLK SG2
D11
 WHT LABEL
D7

WHT VS+
C25
 BLK IP+
C23
 RED IP-/VS-
C24
Primary Heated O2 Sensor
WHT PHO2S
D7
 LT GRN to GRN/BLK SG2
D11
BLK to BLK/YEL HEATER +

BLK to BLK/WHT HEATER -
A6

 

MAP Sensor and TPS

1 2 3

 

MAP Sensor (terminal side)
Pin Wire Color Terminal Name Description
1 RED/GRN MAP Signal D3
2 GRN/WHT SG1 Sensor Ground D12
3 YEL/RED VCC1 Sensor Voltage D4

 

1 2 3

 

TPS (terminal side)
Pin Wire Color Terminal Name Description
1 YEL/BLU VCC2 Sensor Voltage D10
2 RED/BLK TPS Signal D1
3 GRN/BLK SG2 Sensor Ground D11

 

Distributor

1 2 3 4
5 6 7 8
9 10
Distributor C109
Pin Wire Color Terminal Name Description
1 YEL/GRN ICM A20
2 BLU CKP P C2
3 GRN TDC P C3
4 YEL CYP P C4
6 WHT CKP M C12
7 RED TDC M C13
8 BLK CYP M C14
9 BLU TACH Engine Speed Gauge Cluster
10 BLK/YEL Ignition Coil Dash Fuse 9

 

Main Relay

1 2 3
4 5 6 7
Main Relay
Pin Wire Color Terminal Name Description
1 GRN/YEL FLR A16
2 BLU/WHT STS Under dash Fuse 31
3 BLK PG1 G101
4 YEL/GRN FUEL PUMP
5 YEL/GRN IG1 Under dash Fuse 13
6 YEL/BLK IGP1, IGP2 A11, A24, INJ
7 WHT/BLK Constant 12V Under hood Fuse 44

 

Civic Strut Tower Harness

1 2 3 4
5 6 7 8
9 10
Driver's-side strut tower plug C101
Pin Wire Color Terminal Name Description
1 BLK/YEL PHO2S Fuse 15
2 BLK PG Main Relay ground
3 YEL/RED Oil Pressure Switch Gauge warning light
4 BRN/BLK LG SHO2S Ground Shield
5 YEL/BLK Fuel Injectors + from Main Relay
6 WHT/BLU Charge Warning Light
7 YEL/GRN Coolant Temp Signal Temperature Gauge
8 BLU Engine Speed Tachometer to Ignitor
9 BLK/WHT Starter Starter Solenoid
10 BLK/YEL Ignition Distributor

 

Civic Green Harness on ECU

/ / / 4 5 6 7 8 9 10
11 / / 14 15 16 17 18 19 20 21 22
*Vehicle speed signal: VSS → C127 → Speedo → C131 → ECU
Green Plug on top of ECU C131
Pin Wire Color Terminal Name Description
4 RED CLSW Clutch Switch
5 RED/GRN Upshift Light (HX) Manual Transmission
6 GRN FANC Radiator Fan Switch
7 BLU/RED ACS Air Conditioning Switch
8 GRN/ORN MIL Malfunction Indicator Light
9 BRN SCS Service Check Signal
10 WHT/BLU VBU Voltage Backup
11 BLU EVBS Evap Bypass Solenoid
14 GRN/BLK Backup Light Switch On transmission
15 YEL/RED Backup Light Switch On transmission
16 GRN/RED ELD Electric Load Detector
17 GRN/WHT BRKSW Brake Switch
18 BLU/WHT *Speedometer (VSS) C18, Cruise
19 BLK/RED ACC Air Conditioning Clutch
20 GRN/YEL Main Relay
21 LT BLU to BLU/YEL K-Line OBD2 Scan Data
22 BLU/ORN to BLU/WHT STS Starter Signal

 

Integra Strut Tower Harnesses

1 2 3
4 5 6 7
8 9 10 11
12 13 14
*Vehicle speed signal: VSS → C127 → Speedo → C131 → ECU
Driver-side (14 Pin) round plug C305 / C127
Pin Wire Color Terminal Name Description
1 BLK/YEL Alternator From Alternator to Dash Fuse box
2 WHT/BLU Battery Warning Light Gauge Cluster to Alternator
3 RED to RED/YEL PCS A15 B18B1
3 (PNK/BLU) RED to RED/BLU IAB Solenoid A26 GSR B18C1
4 BLK/BLU IACV A12
5 BLK/YEL IG1 (Key) Alternator From Dash Fuse 15 to VSS, VBSOL D5
6 ORN to BLU/WHT *VSS C18, Speedo, Cruise
7 BLU Tachometer Engine Speed ICM to Gauge Cluster
8 YEL/RED Oil Pressure Switch Gauge Cluster
9 GRN FANC A27, Radiator Fan Switch
10 BLK PG1, PG2 A10, A23, G101
11 YEL/GRN Coolant Temp Sending Unit Gauge Cluster
12 YEL/BLK IGP1 / 2 A11, A24 to Junction C125 (IACV, INJ, EVAP, CKF, PHO2S)

 

1 2
3 4
Passenger-side C221 / C101
Pin Wire Color Terminal Name Description
1 RED INJ2 A3
2 BRN INJ1 A4
3 YEL INJ4 A1
4 BLU INJ3 A2

 

1 2 3
4 5 6 7
8 9 10

 

Passenger-side (10 Pin) round plug C222 / C102
Pin Wire Color Terminal Name Description
1 BRN/BLK LG1, 2 A9, A22, G101
2 WHT PHO2S
3 BRN/BLK LG1, 2 A9, A22, G101
4 YEL CYP P C4
5 WHT CYP M C14
6 GRN TDC P C3
7 WHT/BLU - RED TDC M C13
8 BLU CKP P C2
9 BLU/YEL - WHT CKP M C12
10 RED/BLU KS Knock Sensor D6

 

1 2 3
4 5 6 7
8 9 10 11
12 13 14

 

Passenger-side (14 Pin) round plug C223 / C103
Pin Wire Color Terminal Name Description
1 WHT/GRN ALT C A19
2 ORN/BLK - BLK/WHT PO2SHTC A6
3 BLU/RED B18B1 CKF P C1
3 GRN/YEL VTS A8, VTEC Solenoid
4 GRN/WHT SG1 - MAP D12
5 WHT/YEL - RED/GRN MAP D3
6 YEL/WHT - YEL/RED VCC1 - MAP D4
7 WHT/RED B18B1 CKF M C11
7 BLU/BLK VTP SW C15 VTEC Pressure Switch
8 RED/BLK TPS D1
9 GRN/BLU - GRN/BLK SG2 - PHO2S D11
10 YEL/BLU VCC2 - IAT D10
11 YEL/GRN ICM A20
12 RED/YEL IAT D8
13 RED/WHT ECT D2
14 WHT/RED ALT F C17

 

Integra GSR / Type R

1 2 3
USDM harnesses have this plug added for the pins displaced in C103 and C127 by IAB and VTEC wires. If you are using a JDM ECU, you can ignore this plug. If you are swapping a USDM engine, harness, and ECU into an Integra LS/RS/GS, you must run the three wires from this plug to their respective pins on the ECU. At the ECU, You must re-pin A15 to A26 (IAB), and C1 to A8 (VTEC). USDM ECU requires you to also re-pin C12 to C15 (VTP). And in all cases you must add a pin to C102 pin 10 and run it to D6 (Knock).
Passenger-side B18C1/5 C220 / C104
Pin Wire Color Terminal Name Description
1 RED to RED/YEL PCS A15
2 BLU/RED CKF P C1
3 WHT/RED CKF M C11
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