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PCM Inputs and Outputs at PCM Connector C (◦) (49P): Overview

Fig 1: Identifying PCM Inputs And Outputs At PCM Connector C (49P)
G08052435Courtesy of AMERICAN HONDA MOTOR CO., INC.
Terminal number Wire color Terminal name Description Signal
1 BLK PGMETCS (POWER GROUND ETCS) Ground circuit for PCM Less than 0.2 V at all times
2 BLU ETCSM+ (THROTTLE ACTUATOR +SIDE) Drives throttle actuator With ignition switch ON (II): about 0 V
3 GRN ETCSM- (THROTTLE ACTUATOR-SIDE) Ground for throttle actuator With ignition switch ON (II): about 0 V
4 YEL/GRN IG1ETCS (IGNITION SIGNAL ETCS) Detects ignition signal With ignition switch ON (II): battery voltage
5 BLK/WHT SO2SHTCB1 (REAR SECONDARY HEATED OXYGEN SENSOR (REAR SECONDARY HO2S (BANK 1, SENSOR 2) HEATER CONTROL)) Drives rear secondary HO2S (Bank 1, sensor 2) heater With ignition switch ON (II): battery voltage
With warmed up engine running: duty controlled
6 BLK/WHT AFSHTCB1 (REAR AIR FUEL RATIO (REAR A/F) SENSOR (BANK 1, SENSOR 1) HEATER CONTROL) Drives rear A/F sensor (Bank 1, sensor 1) heater With ignition switch ON (II): battery voltage
With warmed up engine running: about 0 V or pulses
7 GRN/RED SO2SHTCB2 (FRONT SECONDARY HEATED OXYGEN SENSOR (SECONDARY HO2S (BANK 2, SENSOR 2) HEATER CONTROL)) Drives front secondary HO2S (Bank 2, sensor 2) heater With ignition switch ON (II): battery voltage
With warmed up engine running: duty controlled
8 GRN/WHT AFSHTCB2 (FRONT AIR FUEL RATIO (FRONT A/F) SENSOR (BANK 2, SENSOR 1) HEATER CONTROL) Drives front A/F sensor (Bank 2, sensor 1) heater With ignition switch ON (II): battery voltage
With warmed up engine running: about 0 V or pulses
9 GRN/WHT SHC (SHIFT SOLENOID VALVE C) Drives shift solenoid valve C With engine running in N and D during no lock-up condition: about 0 V
With engine running in P, R, and D during lock-up condition: battery voltage
10 BLU/RED EGR (EXHAUST GAS RECIRCULATION (EGR) VALVE) Drives EGR valve With EGR operating: duty controlled Without EGR operating: about 0 V


Fig 1: Identifying PCM Inputs And Outputs At PCM Connector C (49P)
G08052436Courtesy of AMERICAN HONDA MOTOR CO., INC.
Terminal number Wire color Terminal name Description Signal
11 YEL/BLU VCC6 (SENSOR VOLTAGE) Provides sensor reference voltage With ignition switch ON (II): about 5.0 V
12 YEL/BLU VCC2 (SENSOR VOLTAGE) Provides sensor reference voltage With ignition switch ON (II): about 5.0 V
14(1) WHT/GRN OP5SW (TRANSMISSION FLUID PRESSURE SWITCH D (5TH CLUTCH)) Detects transmission fluid pressure switch D (5th clutch) signal With ignition switch ON (II):
  • Without 5th clutch pressure: battery voltage
  • With 5th clutch pressure: about 0 V
14(2) WHT/GRN OP5SW (TRANSMISSION FLUID PRESSURE SWITCH D (5TH CLUTCH)) Detects transmission fluid pressure switch D (5th clutch) signal With ignition switch ON (II):
  • Without 5th clutch pressure: about 5.0 V
  • With 5th clutch pressure: about 0 V
15 GRN/RED SG6 (SENSOR GROUND) Sensor ground Less than 0.2 V at all times
16 GRN/YEL SG2 (SENSOR GROUND) Sensor ground Less than 0.2 V at all times
17(1) YEL/GRN ATPD (TRANSMISSION RANGE SWITCH D) Detects transmission range switch D position signal In D: about 0 V
In any position other than D: about 5.0 V
17(2) YEL/GRN ATPD (TRANSMISSION RANGE SWITCH D) Detects transmission range switch D position signal In D: about 0 V
In any position other than D: battery voltage
18(1) BLU/YEL ATPFWD (TRANSMISSION RANGE SWITCH FWD) Detects transmission range switch FWD position signal In D and S: about 0 V
In any position other than D and S: about 5.0 V
18(2) BLU/YEL ATPFWD (TRANSMISSION RANGE SWITCH FWD) Detects transmission range switch FWD position signal In D and S: about 0 V
In any position other than D and S: battery voltage
19(1) RED/WHT ATPRVS (TRANSMISSION RANGE SWITCH RVS) Detects transmission range switch RVS position signal In R: about 0 V
In any position other than R: about 5.0 V
19(2) RED/WHT ATPRVS (TRANSMISSION RANGE SWITCH RVS) Detects transmission range switch RVS position signal In R: about 0 V
In any position other than R: battery voltage
20 BLU/YEL SHA (SHIFT SOLENOID VALVE A) Drives shift solenoid valve A With engine running in 1st and 2nd gears: battery voltage
With engine running in any gear other than 1st and 2nd: about 0 V
21 RED LSA (A/T CLUTCH PRESSURE CONTROL SOLENOID VALVE A) Drives A/T clutch pressure control solenoid valve A With ignition switch ON (II): current controlled
NOTE: Check the label on the PCM to see if it was made by Keihin or Continental. Refer to the GENERAL TROUBLESHOOTING INFORMATION  for more details.
(1) Continental PCM
(2) Keihin PCM


Fig 1: Identifying PCM Inputs And Outputs At PCM Connector C (49P)
G08052437Courtesy of AMERICAN HONDA MOTOR CO., INC.
Terminal number Wire color Terminal name Description Signal
23 WHT/RED SO2SGB1 (REAR SECONDARY HEATED OXYGEN SENSOR (REAR SECONDARY HO2S (BANK 1, SENSOR 2)) SENSOR GROUND) Sensor ground for rear secondary HO2S (Bank 1, sensor 2) With ignition switch ON (II): about 1.5 V
24 RED/YEL IAT (INTAKE AIR TEMPERATURE (IAT) SENSOR) Detects IAT sensor signal With ignition switch ON (II): about 0.1-4.8 V (depending on intake air temperature)
25(1) WHT ATPR (TRANSMISSION RANGE SWITCH R) Detects transmission range switch R position signal In R: about 0 V
In any position other than R: more than 5.0 V
25(2) WHT ATPR (TRANSMISSION RANGE SWITCH R) Detects transmission range switch R position signal In R: about 0 V
In any position other than R: battery voltage
26 RED/BLK ATPN (TRANSMISSION RANGE SWITCH N) Detects transmission range switch N position signal In N: about 0 V
In any position other than N: battery voltage
27(1) BLU/BLK OP2SW (TRANSMISSION FLUID PRESSURE SWITCH A (2ND CLUTCH)) Detects transmission fluid pressure switch A (2nd clutch) signal With ignition switch ON (II):
  • Without 2nd clutch pressure: battery voltage
  • With 2nd clutch pressure: about 0 V
27(2) BLU/BLK OP2SW (TRANSMISSION FLUID PRESSURE SWITCH A (2ND CLUTCH)) Detects transmission fluid pressure switch A (2nd clutch) signal With ignition switch ON (II):
  • Without 2nd clutch pressure: about 5.0 V
  • With 2nd clutch pressure: about 0 V
28 BLU/RED SHB (SHIFT SOLENOID VALVE B) Drives shift solenoid valve B With engine running in 1st, 2nd, and 3rd gears (upshift condition): battery voltage
With engine running in any gear other than 1st, 2nd, 3rd (upshift condition): about 0 V
31(1) WHT/BLK OP6SW (TRANSMISSION FLUID PRESSURE SWITCH E (6TH CLUTCH)) Detects transmission fluid pressure switch E (6th clutch) signal With ignition switch ON (II):
  • Without 6th clutch pressure: battery vltage
  • With 6th clutch pressure: about 0 V
31(2) WHT/BLK OP6SW (TRANSMISSION FLUID PRESSURE SWITCH E (6TH CLUTCH)) Detects transmission fluid pressure switch E (6th clutch) signal With ignition switch ON (II):
  • Without 6th clutch pressure: about 5.0 V
  • With 6th clutch pressure: about 0 V
32 RED/WHT ECT1 (ENGINE COOLANT TEMPERATURE SENSOR (ECT) SENSOR 1) Detects ECT sensor 1 signal With ignition switch ON (II): about 0.1-4.8 V (depending on engine coolant temperature)
33 BLU/YEL TATF (ATF TEMPERATURE SENSOR) Detects AFT temperature signal With ignition switch ON (II): about 0.2-4.0 V (about 1.8 V at operating temperature, depending on ATF temperature)
NOTE: Check the label on the PCM to see if it was made by Keihin or Continental. Refer to the GENERAL TROUBLESHOOTING INFORMATION  for more details.
(1) Continental PCM
(2) Keihin PCM


Fig 1: Identifying PCM Inputs And Outputs At PCM Connector C (49P)
G08052438Courtesy of AMERICAN HONDA MOTOR CO., INC.
Terminal number Wire color Terminal name Description Signal
34 WHT/BLK EGRP (EXHAUST GAS RECIRCULATION (EGR) VALVE POSITION SENSOR) Detects EGR valve position sensor signal With engine running: about 1.2-3.0 V (depending on EGR valve lift)
35 WHT/BLU OPPLSW (LINE PRESSURE SWITCH) Detects line pressure switch signal With ignition switch ON (II):
  • Without line pressure: battery voltage
  • With line pressure: about 0 V
36 BLU SO2SGB2 (FRONT SECONDARY HEATED OXYGEN SENSOR (FRONT SECONDARY HO2S (BANK 2, SENSOR 2)) SENSOR GROUND) Sensor ground for front secondary HO2S (Bank 2, sensor 2) With ignition switch ON (II): about 1.5 V
37(1) BLU/YEL OP4SW (TRANSMISSION FLUID PRESSURE SWITCH C (4TH CLUTCH)) Detects transmission fluid pressure switch C (4th clutch) signal With ignition switch ON (II):
  • Without 4th clutch pressure: battery voltage
  • With 4th clutch pressure: about 0 V
37(2) BLU/YEL OP4SW (TRANSMISSION FLUID PRESSURE SWITCH C (4TH CLUTCH)) Detects transmission fluid pressure switch C (4th clutch) signal With ignition switch ON (II):
  • Without 4th clutch pressure: about 5.0 V
  • With 4th clutch pressure: about 0 V
38(2) BLU/WHT OP3SW (TRANSMISSION FLUID PRESSURE SWITCH B (3RD CLUTCH)) Detects transmission fluid pressure switch B (3rd clutch) signal With ignition switch ON (II):
  • Without 3rd clutch pressure: battery voltage
  • With 3rd clutch pressure: about 0 V
38(2) BLU/WHT OP3SW (TRANSMISSION FLUID PRESSURE SWITCH B (3RD CLUTCH)) Detects transmission fluid pressure switch B (3rd clutch) signal With ignition switch ON (II):
  • Without 3rd clutch pressure: about 5.0 V
  • With 3rd clutch pressure: about 0 V
40 RED/YEL PCS (EVAPORATIVE EMISSION (EVAP) CANISTER PURGE VALVE) Drives EVAP canister purge valve With engine running, engine coolant below 140°F (60°C): battery voltage
With engine running, engine coolant above 140°F (60°C): duty controlled
41 BRN/YEL LG1 (LOGIC GROUND) Ground circuit for PCM Less than 0.2 V at all times
42 WHT/BLU ALTL (ALTERNATOR L SIGNAL) Detects alternator L signal With ignition switch ON (II): about 0 V
With engine running: battery voltage
43 WHT/GRN ALTC (ALTERNATOR CONTROL) Sends alternator control signal With warmed up engine running: about 7.5 V (depending on electrical load)
44 WHT/RED ALTF (ALTERNATOR FR SIGNAL) Detects alternator FR signal With engine running: about 0-5.0 V (depending on electrical load)
45 BLU/YEL OPSW (OIL PRESSURE SWITCH) Detects engine oil pressure signal With ignition switch ON (II): battery voltage
With engine running: about 0 V
NOTE: Check the label on the PCM to see if it was made by Keihin or Continental. Refer to the GENERAL TROUBLESHOOTING INFORMATION  for more details.
(1) Continental PCM
(2) Keihin PCM
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