OBD1 ECU A (26 Pin) C404 Civic, C410 Integra |
Pin |
Wire Color |
Terminal Name |
Description |
Test |
1 |
BRN |
INJ1 |
Injector 1 |
Ignition On: 12V,
Engine running: (-) Pulses |
2 |
YEL |
INJ4 |
Injector 4 |
Ignition On: 12V,
Engine running: (-) Pulses |
3 |
RED |
INJ2 |
Injector 2 |
Ignition On: 12V,
Engine running: (-) Pulses |
4 |
ORN/WHT (Civic) to GRN/YEL |
VTS |
VTEC SOLENOID VALVE |
Low RPM: 0V,
High RPM: 12V |
5 |
LT BLU, BLU (Integra) |
INJ3 |
Injector 3 |
Ignition On: 12V,
Engine running: (-) Pulses |
6 |
ORN/BLK |
PO2SHTC |
Primary O2 Sensor Heater Control |
Ignition On: 12V,
Operating Temperature: 0V |
7 |
GRN/YEL (Civic), GRN/BLU (Integra) |
FLR |
Fuel Relay (Main Relay) |
0V when activated, 12V resting |
8 |
GRN/YEL (Civic), GRN/BLU (Integra) |
FLR |
Fuel Relay (Main Relay) |
Redundant |
9 |
GRN/WHT to BLU/YEL (Civic), BLK/BLU (Integra) |
IACV |
Idle Air Control Valve |
Idle: 6 - 10V |
11 |
ORN/BLU |
EGR Control Solenoid |
Drives EGR valve (VX) |
On: Duty controlled,
Off: 0V |
12 |
YEL/GRN (Civic) to GRN (Integra) |
FANC |
Radiator Fan Switch |
Fan Running: 0V |
13 |
GRN/ORN |
MIL |
Malfunction Indicator Light |
On: 0V, Off: 12V |
15 |
BLK/RED |
ACC |
A/C Compressor Clutch |
AC On: 0V, AC Off: 12V |
16 |
WHT/YEL (Civic), WHT/GRN (Integra) |
ALTC |
Alternator Control |
12 - 0V |
17 |
PNK/BLU (GSR B18C1) |
IAB SOL |
Intake Air Bypass |
Below 5750RPM: 12V |
19 |
WHT |
ICS |
Intake Control Solenoid (H22A) |
|
20 |
RED to RED/BLK to RED |
PCS |
Purge Control Solenoid |
Coolant Temp > 154F: 12V when activated |
21 |
RED/GRN (Civic) YEL/GRN (Integra) |
ICM |
Ignition Control Module |
Key (III): 12V, Engine running: pulses |
22 |
RED/GRN (Civic only) |
ICM |
Ignition Control Module (redundant) |
Key (III): 12V, Engine running: pulses |
23 |
BLK |
PG1 (Main Relay, VTP SW, G101) |
Power Ground 1 |
Less than 1V at all times |
24 |
BLK |
PG2 (Main Relay, VTP SW, G101) |
Power Ground 2 |
Less than 1V at all times |
25 |
YEL/BLK |
IGP2 |
Ignition Power Ground 2, Main Relay, Junction, INJ |
Key (II): 12V |
26 |
BLK/RED (Civic), BRN/BLK (Integra) |
LG1 |
Logic Ground 1 |
Less than 1V at all times |
OBD1 ECU B (16 Pin) C405 Civic, C408 Integra |
Pin |
Wire Color |
Terminal Name |
Description |
Test |
1 |
YEL/BLK |
IGP1 |
Ignition Power 1, Main Relay, Junction, INJ |
Ignition On: 12V |
2 |
BRN/BLK |
LG2 |
Logic Ground 2 |
Less than 1V at all times |
5 |
BLU/RED |
AC Switch (ACS) |
Detects AC switch |
AC switch On: 0V,
AC Switch Off: 12V |
7 |
PNK/BLK |
CLSW |
Clutch Switch (VX) |
|
8 |
BRN/RED (Civic), GRN (Integra) |
PSP SW |
Power Steering Pressure Switch |
When steering: 12V |
9 |
BLU/WHT |
Starter Switch Signal (STS) |
Detects starting, Main Relay |
Engine cranking: 12V |
10 |
YEL/BLU to YEL/WHT (Civic), ORN (Integra) |
VSS |
Vehicle Speed Sensor |
Ignition on, Front wheels rotating: 0 - 5V cycles |
11 |
ORN |
CYP P |
Cylinder Position (Power) |
Engine running: Pulses |
12 |
WHT |
CYP M |
Cylinder Position (Ground) |
|
13 |
ORN/BLU |
TDC P |
Top Dead Center (Power) |
Engine running: Pulses |
14 |
WHT/BLU |
TDC M |
Top Dead Center (Ground) |
|
15 |
BLU/GRN |
CKP P |
Crank Position (Power) |
Engine running: Pulses |
16 |
BLU/YEL |
CKP M |
Crank Position (Ground) |
|
OBD1 ECU D (22 Pin) C405 Civic, C409 Integra |
Pin |
Wire Color |
Terminal Name |
Description |
Test |
1 |
WHT/BLU |
VBU Voltage Backup |
ECU Power source |
12V |
2 |
GRN/WHT |
BKSW |
Brake Switch signal |
Brake pressed: 12V |
3 |
RED/BLU |
KS |
Knock Sensor (GSR, Type R) |
Knock present: pulses |
3 |
BLU/YEL to WHT (Civic VX) |
LAF LABEL |
5-wire O2 Sensor (VX) |
O2 Unplugged, jumpered to D22: .3 - 4.9V |
4 |
BRN (Civic), BRN/WHT (Integra) |
Service Check Signal (SCS) |
Enables Diagnostic mode |
Jumpered: 0V,
Not jumpered: 5V or Battery voltage |
6 |
ORN/BLU (Civic) to BLU/BLK |
VTP SW (USDM) |
VTEC Pressure Switch |
VTEC ON: 12V |
7 |
LT BLU |
DLC |
Data Link Connector |
|
8 |
WHT/BLU (Civic VX) |
LAF VS+ |
5-wire O2 Sensor (VX) |
Jumpered to D22: > .5V |
9 |
PNK to BLU (Civic), WHT/RED (Integra) |
ALT F |
Alternator FR Signal |
Engine running: voltage dependent on electrical load |
10 |
GRN/RED |
ELD |
Electric Load Detector |
Parking Lights On, Idle: 2.5 - 3.5V, Headlights On: 1.5 - 2.5V |
11 |
LT GRN to RED/BLU (Civic), RED/BLK (Integra) |
TPS |
Throttle Position Sensor |
Fully Open: 4.8V,
Closed: .5V |
12 |
WHT/BLK |
EGRL (VX) |
Exhaust Gas Recirculation Valve Position |
Idle: 1.2V |
13 |
RED/WHT |
ECT |
Engine Coolant Temp |
.1 - 4.8V |
14 |
WHT (Civic), WHT/RED (Integra) |
PHO2S |
Primary Heated O2 Sensor Signal |
Full throttle, Operating temperature > .6V, Decel > .4V |
14 |
ORN/BLU (Civic VX) |
LAF IP+ |
5-wire O2 (VX) |
|
15 |
RED/YEL |
IAT |
Intake Air Temperature |
.1 - 4.8V |
16 |
BLU/GRN to ORN (Civic VX) |
LAF IP-, VS- |
5-wire O2 (VX) |
Jumpered TO D22: > .5V |
17 |
WHT (Civic) or WHT/YEL (Integra) |
MAP |
Manifold Absolute Pressure |
Ignition on: 3V, Idle: ~1V |
18 |
PNK/GRN to LT BLU |
SIL |
Upshift Light (CX, VX) |
|
19 |
YEL/GRN (Civic) or YEL/WHT to YEL/RED (Integra) |
VCC1 |
Sensor Voltage 1 (MAP) |
Ignition on: 5V |
20 |
YEL/WHT (Civic), YEL/BLU (Integra) |
VCC2 |
Sensor Voltage 2 (TPS) |
Ignition on: 5V |
21 |
GRN/BLU (Civic) to GRN/WHT (Integra) |
SG1 |
Sensor Ground 1 |
Less than 1V at all times |
22 |
GRN/WHT (Civic), GRN/BLU (Integra) |
SG2 |
Sensor Ground 2 |
Less than 1V at all times |