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Home >> Honda >> 2021 >> Civic EX, 4D Hatchback >> Repair and Diagnosis >> Engine Performance >> Engine Control Systems >> Engine Control / Engine Mechanical - Service, Testing & Troubleshooting >> Connector View >> PCM Connector for Inputs and Outputs (K20C2)
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PCM Connector for Inputs and Outputs (K20C2)

Connector Index
PCM Connector A (50P)
PCM Connector E (80P)

PCM Inputs and Outputs at PCM Connector A (50P) 

GHH406737Courtesy of HONDA, U.S.A., INC.
Terminal number Terminal name Description
1 Not used  
2 Not used  
3 Not used  
4 SO2HT (SECONDARY HEATED OXYGEN SENSOR (SECONDARY HO2S) (SENSOR 2) HEATER CONTROL) Drives secondary HO2S (Sensor 2) heater
5 FI MAIN RLY CL- (PGM-FI MAIN RELAY 1) Drives PGM-FI main relay 1
6 *1 VSV (EVAPORATIVE EMISSION (EVAP) CANISTER VENT SHUT VALVE) Drives EVAP canister vent shut valve
7 +B BACKUP FI-ECU (VOLTAGE BACK UP) Power source for PCM memory
8 FI MAIN RLY OUT (POWER SOURCE) Power source for PCM
9 Not used  
10 LIN (BATT SENSOR) (LOCAL INTERCONNECT NETWORK) Sends and receives communication signal
11 FUEL PUMP RLY CL- (IMMOBILIZER FUEL PUMP RELAY) Drives PGM-FI main relay 2
12 Not used  

*1: USA and Canada models

*2: With keyless access system

*3: CVT

*4: M/Tt

*5: With A/C

*6: With display audio

*7: Without multipurpose camera unit

*8: With multipurpose camera unit

Terminal number Terminal name Description
13 FI ECU GND (GROUND) Ground for PCM
14 Not used  
15 *2 ST CUT RLY1 CL- (STARTER CUT RELAY 1) Drives starter cut relay 1
16 FI SUB RLY OUT (POWER SOURCE) Power source for PCM
17 FAN CONTROL (RFC UNIT CONTROL) Drives RFC unit
18 Not used  
19 *2 ST RLY 1 TO 2 (STARTER CUT RELAY RETURN SIGNAL) Detects starter cut relay signal
20 *3 TM-CAN_L (TM-CAN COMMUNICATION SIGNAL LOW) Sends and receives communication signal for TCM
21 *3 TM-CAN_H (TM-CAN COMMUNICATION SIGNAL HIGH) Sends and receives communication signal for TCM
21 *2*4 CLUTCH SW (SA) (CLUTCH PEDAL POSITION SWITCH A SIGNAL) Detects clutch pedal position switch A signal
22 Not used  
23 *2 ST CUT RLY2 CL- (STARTER CUT RELAY 2) Drives starter cut relay 2
24 Not used  
25 FI SUB RLY CL- (PGM-FI SUBRELAY) Drives PGM-FI subrelay
26 STOP SW (BRAKE PEDAL POSITION SWITCH) Detects brake pedal position switch signal
27 SCS (SERVICE CHECK SIGNAL) Detects service check signal
28 *2 STS (STARTER SWITCH SIGNAL) Detects starter switch signal
29 Not used  
30 RFC RLY CL- (RFC RELAY) Drives RFC relay
31 Not used  
32 APS1 (ACCELERATOR PEDAL POSITION (APP) SENSOR A) Detects APP sensor A signal
33 *5 PD SENSOR (A/C PRESSURE SENSOR) Detects A/C pressure sensor signal
34 APS2 (ACCELERATOR PEDAL POSITION (APP) SENSOR B) Detects APP sensor B signal
35 *4*6 VSP (VEHICLE SPEED SIGNAL OUTPUT) Sends vehicle speed signal
36 *7 F-CAN_L (CAN COMMUNICATION SIGNAL LOW) Sends and receives communication signal
36 *8 F-CAN A_L (CAN COMMUNICATION SIGNAL LOW) Sends and receives communication signal
37 *7 F-CAN_H (CAN COMMUNICATION SIGNAL HIGH) Sends and receives communication signal
37 *8 F-CAN A_H (CAN COMMUNICATION SIGNAL HIGH) Sends and receives communication signal
38 *8 F-CAN B_L (CAN COMMUNICATION SIGNAL LOW) Sends and receives communication signal
39 *8 F-CAN B_H (CAN COMMUNICATION SIGNAL HIGH) Sends and receives communication signal
40 S-NET (SERIAL COMMUNICATION FOR IMMOBILIZER) Sends serial communication signal
41 Not used  
42 *1 PTANK (FUEL TANK PRESSURE (FTP) SENSOR) Detects FTP sensor signal
43 SG5 (SENSOR GROUND) Sensor ground
44 VCC5 (SENSOR VOLTAGE) Provides sensor reference voltage
45 VCC4 (SENSOR VOLTAGE) Provides sensor reference voltage
46 SG4 (SENSOR GROUND) Sensor ground
47 SO2 (SECONDARY HEATED OXYGEN SENSOR (SECONDARY HO2S) (SENSOR 2)) Detects secondary HO2S (Sensor 2) signal
48 SO2 SG (SECONDARY HEATED OXYGEN SENSOR (SECONDARY HO2S) (SENSOR 2) SENSOR GROUND) Sensor ground for secondary HO2S (Sensor 2)
49 BKSWNC (BRAKE PEDAL POSITION SWITCH) Detects brake pedal position switch signal
50 Not used  

*1: USA and Canada models

*2: With keyless access system

*3: CVT

*4: M/Tt

*5: With A/C

*6: With display audio

*7: Without multipurpose camera unit

*8: With multipurpose camera unit

PCM Inputs and Outputs at PCM Connector E (80P) 

GHH406738Courtesy of HONDA, U.S.A., INC.
Terminal number Terminal name Description
1 Not used  
2 Not used  
3 Not used  
4 Not used  
5 Not used  
6 Not used  
7 Not used  
8 Not used  
9 Not used  
10 Not used  
11 Not used  
12 Not used  
13 AFHT (AIR FUEL RATIO (A/F) SENSOR (SENSOR 1) HEATER CONTROL) Drives A/F sensor (Sensor 1) heater
14 Not used  
15 Not used  
16 Not used  

*1: M/T

*2: With A/C

*3: USA and Canada models

*4: CVT with keyless access system

Terminal number Terminal name Description
17 Not used  
18 INJ1 (No. 1 INJECTOR) Drives No. 1 injector
19 INJ4 (No. 4 INJECTOR) Drives No. 4 injector
20 INJ3 (No. 3 INJECTOR) Drives No. 3 injector
21 INJ2 (No. 2 INJECTOR) Drives No. 2 injector
22 PG (GROUND) Ground for PCM
23 PG (COIL) (GROUND) Ground for PCM
24 GND2 (GROUND) Ground for PCM
25 Not used  
26 Not used  
27 MTR1 (THROTTLE ACTUATOR) Drives throttle actuator
28 MTR2 (THROTTLE ACTUATOR) Drives throttle actuator
29 *1 RVS LCK (REVERSE LOCKOUT SOLENOID) Drives reverse lockout solenoid
30 Not used  
31 *2 ACC (A/C COMPRESSOR CLUTCH RELAY) Drives A/C compressor clutch relay
32 CAM (CAMSHAFT POSITION (CMP) SENSOR B) Detects CMP sensor B signal
33 Not used  
34 KS GND (KNOCK SENSOR GROUND) Sensor ground for knock sensor
35 KNOCK (KNOCK SENSOR) Detects knock sensor signal
36 IG1 (MONI) Detects ignition signal
37 IGN01 (No. 1 IGNITION COIL PULSE) Drives No. 1 ignition coil
38 IGN02 (No. 2 IGNITION COIL PULSE) Drives No. 2 ignition coil
39 IGN03 (No. 3 IGNITION COIL PULSE) Drives No. 3 ignition coil
40 IGN04 (No. 4 IGNITION COIL PULSE) Drives No. 4 ignition coil
41 Not used  
42 Not used  
43 TDC (CAMSHAFT POSITION (CMP) SENSOR A) Detects CMP sensor A signal
44 CRANK (CRANKSHAFT POSITION (CKP) SENSOR) Detects CKP sensor signal
45 SG6 (SENSOR GROUND) Sensor ground
46 VTC EX (VTC OIL CONTROL SOLENOID VALVE B) Drives VTC oil control solenoid valve B
47 Not used  
48 IP (AIR FUEL RATIO (A/F) SENSOR (SENSOR 1) IP CELL) Detects A/F sensor (Sensor 1) pump cell
49 Not used  
50 THL1 (THROTTLE POSITION (TP) SENSOR A) Detects TP sensor A signal
51 THL2 (THROTTLE POSITION (TP) SENSOR B) Detects TP sensor B signal
52 TW (ENGINE COOLANT TEMPERATURE (ECT) SENSOR 1) Detects ECT sensor 1 signal
53 TA (INTAKE AIR TEMPERATURE (IAT) SENSOR) Detects IAT sensor signal
54 TW2 (ENGINE COOLANT TEMPERATURE (ECT) SENSOR 2) Detects ECT sensor 2 signal
55 Not used  
56 PB (MANIFOLD ABSOLUTE PRESSURE (MAP) SENSOR) Detects MAP sensor signal
57 Not used  
58 ENG OP SW (OIL PRESSURE SWITCH) Detects oil pressure switch signal
59 *3 VTM (ROCKER ARM OIL PRESSURE SWITCH) Detects rocker arm oil pressure switch signal
60 Not used  
61 VGP (MASS AIR FLOW (MAF) SENSOR) Detects MAF sensor signal
62 Not used  
63 VCC6 (SENSOR VOLTAGE) Provides sensor reference voltage

*1: M/T

*2: With A/C

*3: USA and Canada models

*4: CVT with keyless access system

Terminal number Terminal name Description
64 VTC IN (VTC OIL CONTROL SOLENOID VALVE A) Drives VTC oil control solenoid valve A
65 VTS (ROCKER ARM OIL CONTROL SOLENOID) Drives rocker arm oil control solenoid
66 *1 NC (OUTPUT SHAFT (COUNTERSHAFT) SPEED SENSOR) Detects output shaft (countershaft) speed sensor signal
67 *4 ATP ST (TRANSMISSION RANGE SWITCH P/N POSITION) Detects transmission range switch P/N position signal
67 *1 NSS1 (NEUTRAL POSITION SENSOR SIGNAL) Detects neutral position sensor signal
68 *1 NSS2 (NEUTRAL POSITION SENSOR SIGNAL) Detects neutral position sensor signal
69 Not used  
70 VCC1 (SENSOR VOLTAGE) Provides sensor reference voltage
71 SG1 (SENSOR GROUND) Sensor ground
72 Not used  
73 VS (AIR FUEL RATIO (A/F) SENSOR (SENSOR 1) VS CELL) Detects A/F sensor (Sensor 1) VS cell
74 VCENT (AIR FUEL RATIO (A/F) SENSOR (SENSOR 1) VIRTUAL GROUND) Provides reference voltage for A/F sensor (Sensor 1)
75 VCC3 (DBW) (SENSOR VOLTAGE) Provides sensor reference voltage
76 SG3 (DBW) (SENSOR GROUND) Sensor ground
77 VCC2 (SENSOR VOLTAGE) Provides sensor reference voltage
78 SG2 (SENSOR GROUND) Sensor ground
79 Not used  
80 PCS (EVAPORATIVE EMISSION (EVAP) CANISTER PURGE VALVE) Drives EVAP canister purge valve

*1: M/T

*2: With A/C

*3: USA and Canada models

*4: CVT with keyless access system