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OBD2B Honda ECU Pinout

1999-2000 Civic

2000-2001 Integra

/ 2 3 4 5 6 / 8 9 10 /
12 13 14 15 16 17 18 19 20 21 / 23 24
25 26 27 28 29 30 / 32
*Pin must be moved from A16 to A15 when using a '99-00 Civic harness on a '00-01 Integra ECU
OBD2B ECU A (32 Pin) C132 Civic, C408 Integra
Pin Wire Color Terminal Name Description Test
2 GRN/WHT MCS (Accord) Engine Mount Control Solenoid Idle: 0V Above Idle: Battery Voltage
3 BLU 2WBS EVAP Bypass Solenoid Ignition On: Battery Voltage
4 LT GRN/WHT (LT GRN Integra) VSV Vent Shut Valve (EVAP Canister) Ignition On: Battery Voltage
5 BLU/GRN CRS Cruise Control Signal Ignition On: pulses
6 RED/YEL (RED Integra) PCS Purge Control Solenoid Coolant Temp > 154F: 12V when activated
8 BLK/WHT (GRN/RED Integra) SO2SHTC Secondary O2 Sensor Heater Control Ignition On: 12V Operating Temp: Duty controlled
10 BRN (BRN/WHT Integra) Service Check Signal (SCS) Enables Diagnostic mode Jumpered: 0V, Not jumpered: 5V or Battery voltage
12 PNK IMOLMP (Accord, Integra) Imobilizer Lamp On: 0V Off: Battery Voltage
13 BLU IMOEN (Accord, Integra) Imobilizer Enabled
15* GRN/YEL FLR Fuel Relay (Main Relay) ECUs with Immobilizers
16* GRN/YEL FLR Fuel Relay (Main Relay) 0V when activated, 12V resting
17 RED (BLK/RED Integra) ACC Air Conditioning Clutch AC On: 0V, AC Off: 12V
18 GRN/ORN MIL Malfunction Indicator Light On: 0V, Off: 12V
19 BLU NEP (Tachometer) Engine Speed Engine Running: pulses
20 GRN FANC Radiator Fan Switch Fan Running: 0V
21 GRY (GRN/WHT Integra) K-Line OBD2 Scan Signal Ignition on: Battery Voltage
23 WHT/RED (BLU/RED Integra) SHO2S Secondary Heated O2 sensor signal Full throttle, operating temp: 0.6V, Deceleration: 0.4V
24 BLU/ORN (BLU/WHT Integra) Starter Switch Signal (STS) Detects starting Engine cranking: 12V
25 RED IMOCD Imobilizer Code
26 GRN PSP SW Power Steering Pressure Switch When steering: 12V
27 BLU/RED AC Switch (ACS) Detects AC switch AC switch On: 0V, AC Switch Off: 12V
29 LT GRN PTANK Fuel Tank Pressure sensor Gas Cap Off: 2.5V
30 GRN/RED ELD Electric Load Detector Parking Lights On, Idle: 2.5 - 3.5V, Headlights On: 1.5 - 2.5V
32 WHT/BLK (GRN/WHT Integra) BKSW Brake Switch signal Brake pressed: 12V
1 2 3 4 5 / 7 8
9 10 11 12 13 14 16 17 18
19 20 21 22 23 24 25
OBD2B ECU B (25 Pin) C133 Civic, C457 Integra
Pin Wire Color Terminal Name Description Test
1 YEL/BLK IGP1 Ignition Power 1 Ignition On: 12V
2 BLK PG1 Power Ground 1 Less than 1V at all times
3 RED INJ2 Injector 2 Ignition On: 12V, Engine running: (-) Pulses
4 BLU INJ3 Injector 3 Ignition On: 12V, Engine running: (-) Pulses
5 YEL INJ4 Injector 4 Ignition On: 12V, Engine running: (-) Pulses
6* BLK/BLU IACV + (D16Y7, automatic) 3-Wire IACV Positive De-pin and move to B23
7 PNK E-EGR Drives EGR valve On: Duty controlled Off: 0V
9 YEL/BLK IGP2 Ignition Power Ground 2 Key (II): 12V
10 BLK PG2 Power Ground 2 Less than 1V at all times
11 BRN INJ1 Injector 1 Ignition On: 12V, Engine running: (-) Pulses
12 GRN/YEL VTS VTEC SOLENOID VALVE Low RPM: 0V, High RPM: 12V
13 YEL/GRN ICM Ignition Control Module Key (III): 12V, Engine Running: pulses
14 BLU/BLK OP2SW 2nd Oil Pressure Switch Ignition On: 5V
15* ORN IACV - (D16Y7, automatic) 3-Wire IACV Negative De-pin and leave hanging
16 GRN/RED PO2SHTCR Primary O2 Sensor Heater Control Relay Ignition On: 0V
16 PNK/BLU IAB Solenoid Intake Air Bypass Solenoid (GSR B18C1) Above 5750: 0V, Below 5750: 12V
19 BLK/WHT PO2SHTC Primary O2 Sensor Heater Control Ignition On: 12V, Operating Temperature: 0V
20 BRN/BLK LG1 Logic Ground 1 Less than 1V at all times
21 WHT/YEL (WHT/BLU Integra) VBU Voltage Backup ECU Power source 12V
22 BRN/BLK LG2 Logic Ground 2 Less than 1V at all times
23 BLK/BLU IACV Idle Air Control Valve Idle: 6 - 10V
1 2 3 / 5 6 7 8 9 10
/ / 13 14 15 16 17 18 19 20 21 /
23 24 25 26 27 28 29 30 31
OBD2B ECU C (31 Pin) C134 Civic, C409 Integra
Pin Wire Color Terminal Name Description Test
1 BLK/WHT (BRN/BLK Integra) PO2SHTC Primary O2 Sensor Heater Control Ignition On: 12V, Operating Temperature: duty controlled
2 WHT/GRN ALTC Alternator Control 12 - 0V
3 RED/BLU KS Knock Sensor (GSR, Type R) Knock present: pulses
5 WHT/RED ALT F Alternator FR Signal Engine running: voltage dependent on electrical load
6 WHT/BLK EGRL Exhaust Gas Recirculation Valve Position Idle: 1.2V
7 GRN/WHT SG1 Sensor Ground 1 Less than 1V at all times
8 BLU CKP P Crank Position (Power) Engine Running: pulses
9 WHT (BLU/YEL Integra) CKP M Crank Position (Ground)
10 BLU/BLK VTP SW (USDM) VTEC Pressure Switch VTEC ON: 12V
13 WHT PO2SHTC Primary O2 Sensor Heater Control Ignition On: 12V
14 RED PHO2S+ Primary Heated O2 Sensor Signal + Full throttle, Operating temperature > .6V, Decel > .4V
15 BLU PHO2S- Primary O2 Sensor Signal -
16 WHT PHO2S Primary O2 Sensor Signal Operating temp, Full throttle: above .6V, Off throttle: below .4V
17 RED/GRN (WHT/YEL Integra) MAP Manifold Absolute Pressure Ignition on: 3V, Idle: ~1V
18 GRN/BLK (GRN/BLU Integra) SG2 Sensor Ground 2 Less than 1V at all times
19 YEL/RED VCC1 Sensor Voltage 1 (MAP) Ignition on: 5V
20 GRN TDC P Top Dead Center (Power) Engine Running: pulses
21 RED (WHT/BLU Integra) TDC M Top Dead Center (Ground)
22 BLU/RED CKF P Crank Speed Fluctuation Power Engine Running: pulses
23 BLU/WHT (ORN Integra) VSS Vehicle Speed Sensor Ignition on, Front wheels rotating: 0 - 5V cycles
25 RED/YEL IAT Intake Air Temperature .1 - 4.8V
26 RED/WHT ECT Engine Coolant Temp .1 - 4.8V
27 RED/BLK TPS Throttle Position Sensor Fully Open: 4.8V, Closed: .5V
28 YEL/BLU VCC2 Sensor Voltage 2 Ignition on: 5V
29 YEL CYP P Cylinder Position (Power) Engine Running: pulses
30 BLK (WHT Integra) CYP M Cylinder Position (Ground)
31 WHT/RED CKP M Crankshaft Fluctuation Ground

O2 Sensor

Primary Heated O2 Sensor
WHT PHO2S
C16
 GRN to GRN/BLK SG2
Junction
BLK to BLK/YEL HEATER +
Under dash Fuse 15
 BLK to BLK/WHT HEATER -
C1

MAP Sensor and TPS

1 2 3
MAP Sensor (terminal side)
Pin Wire Color Terminal Name Description
1 RED/GRN MAP Signal C17
2 GRN/WHT SG1 Sensor Ground C7
3 YEL/RED VCC1 Sensor Voltage C19
1 2 3
TPS (terminal side)
Pin Wire Color Terminal Name Description
1 YEL/BLU VCC2 Sensor Voltage C28
2 RED/BLK TPS Signal C27
3 GRN/BLK SG2 Sensor Ground C18

Distributor

1 2 3 4
/ 6 7 8
Distributor C120 Civic, C109 Integra
Pin Wire Color Terminal Name Description
1 YEL/GRN ICM B13
2 LT BLU or BLU/GRN to BLU CKP P C8
3 ORN/BLU to GRN TDC P C20
4 ORN to YEL CYP P C29
6 BLU/YEL to WHT CKP M C9
7 WHT/BLU to RED TDC M C21
8 WHT to BLK CYP M C30

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 B1, B9, 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

1 2 3 4 5 6 7 8 9 10
11 12 / 14 15 16 17 18 19 20 21 22
*Vehicle speed signal: VSS → C127 → Speedo → C131 → ECU
Green Harness on top of ECU C131
Pin Wire Color Terminal Name Description
1 LT GRN PTANK Fuel Tank Pressure Sensor
2 GRN/WHT SG2 SHO2S
3 WHT/RED SHO2S Secondary Heated O2 Sensor Signal
5 YEL/BLU VCC2 D10 to PTANK
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
12 BLK/WHT SHO2SHTC Rear O2 Sensor
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) C23, 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 /
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 Fuse 15 (C438 pin 13)
2 WHT/BLU Battery Warning Light Gauge Cluster to Alternator
3 RED to RED/YEL PCS A6 B18B1
3 (PNK/BLU) RED to RED/BLU IAB Solenoid (ECU Plug B16)
4 BLK/BLU IACV B23
5 BLK/YEL IG1 (Key) Alternator From Dash Fuse 15 pin 12 to VSS, EVAP, IAB, ELD
6 ORN to BLU/WHT *VSS C23, Speedo, Cruise
8 YEL/RED Oil Pressure Switch Gauge Cluster
9 GRN FANC A20, Radiator Fan Switch
10 BLK PG1, PG2 B2, B10, G101
11 YEL/GRN Coolant Temp Sending Unit Gauge Cluster
12 YEL/BLK IGP1 / 2 B1, B9 to Junction C125 (IACV, INJ, EVAP, CKF, PHO2S)
13 GRN/BLK LCB (AUTO) D3
14 YEL LCA (AUTO) D1
1 2
3 4
Passenger-side C221 / C101
Pin Wire Color Terminal Name Description
1 RED INJ2 B3
2 BRN INJ1 B11
3 YEL INJ4 B5
4 BLU INJ3 B4
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 LG 1 or 2 B20 or 22 Thermostat Housing
2 WHT PHO2S D14
3 BRN/BLK LG 1 or 2 B20 or 22 Thermostat Housing
4 YEL CYP P C29
5 WHT CYP M C30
6 GRN TDC P C20
7 WHT/BLU - RED TDC M C21
8 BLU CKP P C8
9 BLU/YEL - WHT CKP M C9
10 RED/BLU KS Knock Sensor C3
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 C2
2 ORN/BLK - BLK/WHT PO2SHTC C1
3 BLU/RED B18B1 CKF P C22
3 GRN/YEL VTS B12 VTEC Solenoid
4 GRN/WHT SG1 - MAP C7
5 WHT/YEL - RED/GRN MAP C17
6 YEL/WHT - YEL/RED VCC1 - MAP C19
7 WHT/RED B18B1 CKF M C31
7 BLU/BLK VT PSW C10 VTEC Pressure Switch
8 RED/BLK TPS C27
9 GRN/BLU - GRN/BLK SG2 - PHO2S C18
10 YEL/BLU VCC2 - IAT C28
11 YEL/GRN ICM B13
12 RED/YEL IAT C25
13 RED/WHT ECT C26
14 WHT/RED ALT F C5

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 A6 to B16 (IAB), and C22 to B12 (VTEC). USDM ECU requires you to also re-pin C31 to C10 (VTP). And in all cases you must add a pin to C102 pin 10 and run it to C3 (Knock).
Passenger-side B18C1/5 C220 / C104
Pin Wire Color Terminal Name Description
1 RED to RED/YEL PCS A6
2 BLU/RED CKF P C22
3 WHT/RED CKF M C31