2001-2003 Honda Civic ECU Wiring


Connector A (31 Pins)
1-blk/wht-Primary O2 sensor heater control
2-yel/blk-Power Source
3-yel/blk-Power source
4-blk-Power ground
5-blk-Power ground
6-wht-Primary O2 sensor
7-blu-Crankshaft position
8-yel-Sensor return volt
9-red/blu-Knock sensor
10-grn/yel-Sensor ground
11-grn/wht-Sensor ground
12-blk/red-Idle air control valve
13-wht/blk-EGR Valve position VTEC ONLY
14-blk/wht-Secondary O2 sensor heater control
15-red/blk-Throttle position sensor
18-wht/grn-Vehicle speed sensor
19-grn/red-MAP Sensor
20-yel/blu-Sensor Voltage Supply
21-yel/red-Sensor Voltage Supply
23-brn/yel-Logic ground
24-brn/yel-logic ground
25-wht/red-Secondary O2 Sensor
26-grn-Top dead center sensor
27-brn-Igniton coil 4
28-wht/blu-coil 3
29-blu/red-coil 2
30-yel/grn-coil 1

Connector B (24 Pins)
2-yel-Fuel injector 4
3-blu-Fuel Injector 3
4-red-Fuel Injector 2
5-brn-Fuel Injector 1
6-grn-Radiator fan control
7-red/blk-A/T Pressure control solenoid valve A
8-red/wht-Engine Coolant sensor
9-blu/blk-VTEC Oil pressure switch VTEC ONLY
10-wht/blu-Alternator L Signal
13-wht/red-Alternator FR Signal
14-blu/red-EGR Valve VTEC ONLY
15-grn/yel-VTEC Solenoid valve
16-blk/red-A/T Pressure control solenoid valve B
17-red/yel-Intake air temp sensor
18-wht/grn-Alternator control
21-yel/blu-EVAP Canistor purge valve



Connector C (22 Pins)– AUTO TRANSMISSION ONLY
1-wht/blk-A/T Pressure control solenoid valve A
2-yel/blu-Torque converter clutch solenoid
4-grn/wht-Shift solenoid B
6-blu/blk-Shift Solenoid A
7-wht/red-Mainshaft speed sensor
8-brn/wht-A/T Pressure control solenoid valve B
9-red-Position switch D3
10-wht-position switch R
11-blu-position switch 2
12-blu/wht-position switch neutral or park
14-grn-countershaft speed sensor ground
15-blu-countershaft speed sensor
18-blu/yel-position switch D3 or D
20-yel-position switch D
21-wht/grn-mainshaft speed sensor ground

Connector E (31 pins)
1-grn/yel-Immobilizer fuel pump relay
2-wht/red-Secondary O2 Sensor EX Only
3-brn/yel-Logic ground
4-pnk-Sensor ground
5-yel/blu-Sensor voltage source
6-blk/wht-Secondary O2 sensor heater control EX Only
7-red/yel-PGM-FI main relay 1
9-yel/blk-Ignition input signal
12-blu/orn-Cruise control signal
13-wht/blu-Interlock control unit
14-lt grn-Fuel tank pressure sensor
15-grn/red-Electrical load detector
16-lt grn/blk-Power steering pressure switch
18-red-A/C Clutch
20-blu/red-EVAP bypass solenoid valve
21-lt grn/red-EVAP Canister shut valve
22-wht/blk-Brake pedal position switch
23-lt blu-K line
24-yel-Multiplex control unit comm line
26-blu-Engine speed pulse
27-red/blu-Immobilizer code
29-brn-Service check signal
30-red/wht-Write enable signal
31-grn/orn-MIL or check engine light enable