ECM/PCM Inputs and Outputs at Connector E (31P)

Fig 1: Identifying ECM/PCM Inputs And Outputs Connector E (31P) Terminals

Courtesy of AMERICAN HONDA MOTOR CO., INC.

NOTE: Standard battery voltage is about 12 V.

BATTERY VOLTAGE SPECIFICATION

Terminal number

Wire color

Terminal name

Description

Signal

LT BLU

ECT2 (ENGINE COOLANT TEMPERATURE SENSOR 2)

Detects ECT sensor 2 signal

With ignition switch ON (II): about 0.1-4.8 V (depending on engine coolant temperature)
With fully warmed up engine: about 0.5-0.7 V

2⁽¹⁾

BRN/WHT

SLS (SHIFT LOCK SOLENOID)

Drives shift lock solenoid

With ignition switch ON (II), in the P position, brake pedal pressed, and accelerator released: about 0 V

BRN/YEL

LG3 (LOGIC GROUND)

Ground for ECM/PCM control circuit

Less than 0.5 V at all times

PNK

SG4 (SENSOR GROUND)

Sensor ground

Less than 0.5 V at all times

ORN

VCC4 (SENSOR VOLTAGE)

Provides sensor voltage

With ignition switch ON (II): about 5.0 V
With ignition switch OFF: about 0 V

6⁽⁴⁾

BLU

TAC

Detects evaporator sensor signal

With ignition switch ON (II): about 0.1-4.8 V (depending on evaporator temperature)

RED/YEL

MRLY (PGM-FI MAIN RELAY)

Drives PGM-FI main relay 1 (Fl MAIN) Power source for DTC memory

With ignition switch ON (II): about 0 V
With ignition switch OFF: battery voltage

PNK/BLK

AFSHTCR (AIR FUEL RATIO (A/F) SENSOR HEATER CONTROL RELAY)

Drives A/F sensor relay

With ignition switch ON (II): about 0 V

BLK/YEL

IG1 (IGNITION SIGNAL)

Detects ignition signal

With ignition switch ON (II): battery voltage
With ignition switch OFF: about 0 V

WHT

CANH(CAN COMMUNICATION SIGNAL HIGH)

Sends communication signal

With ignition switch ON (II): about 2.5 V (pulses)

GRN

FANC (RADIATOR FAN CONTROL)

Drives radiator fan relay

With radiator fan running: about 0 V
With radiator fan stopped: battery voltage

LTGRN

FTP (FUEL TANK PRESSURE (FTP) SENSOR)

Detects FTP sensor signal

With ignition switch ON (II) and fuel fill cap removed: about 2.5 V

15⁽³⁾

BLU/ORN

ELD (ELECTRICAL LOAD DETECTOR)

Detects ELD signal

With ignition switch ON (II): about 0.1-4.8 V (depending on electrical load)

16⁽²⁾

YEL

SUPP (PADDLE SHIFTER+ (UPSHIFT SWITCH))

Detects (paddle shifter+ (upshift switch)) signal

With paddle shifter+ (upshift switch) puled: about 0 V
With paddle shifter+ (upshift switch) released: battery voltage

GRN/YEL

IMOFPR (IMMOBILIZER FUEL PUMP RELAY)

Drives PGM-FI main relay 2 (FUEL PUMP)

About 0 V for 2 seconds after turning ignition switch ON (II), then battery voltage With the engine running: about 0 V

18⁽⁴⁾

RED

ACC (A/C COMPRESSOR CLUTCH RELAY)

Drives A/C compressor clutch relay

With compressor ON: about 0 V
With compressor OFF: battery voltage

⁽¹⁾

A/T

⁽²⁾	A/T (5-position)

⁽³⁾	USA, '08 Canada (M/T) models

⁽⁴⁾

With A/C

ECM/PCM Inputs and Outputs at Connector E (31P)

Fig 2: Identifying ECM/PCM Inputs And Outputs Connector E (31P) Terminals

Courtesy of AMERICAN HONDA MOTOR CO., INC.

NOTE: Standard battery voltage is about 12 V.

BATTERY VOLTAGE SPECIFICATION

Terminal number

Wire color

Terminal name

Description

Signal

LTGRN/RED

VSV (EVAPORATIVE EMISSION (EVAP) CANISTER VENT SHUT VALVE)

Drives EVAP canister vent shut valve

With ignition switch ON (II): battery voltage

WHT/RED

SHO2S (SECONDARY HEATED OXYGEN SENSOR (SECONDARY HO2S), SENSOR 2)

Detects secondary HO2S (sensor 2) signal

With throttle fully closed at idle and fully warmed up engine: above 0.6 V
With throttle quickly closed: below 0.4 V

BLK/WHT

SO2SHTC (SECONDARY HEATED OXYGEN SENSOR (SECONDARY HO2S) HEATER CONTROL)

Drives secondary HO2S heater

With ignition switch ON (II): battery voltage With fully warmed up engine running: duty controlled

WHT/BLK

BKSW (BRAKE PEDAL POSITION SWITCH)

Detects brake pedal position switch signal

With brake pedal released: about 0 V
With brake pedal pressed: battery voltage

RED

CANL (CAN COMMUNICATION SIGNAL LOW)

Sends communication signal

With ignition switch ON (II): about 2.5 V (pulses)

GRN/ORN

NEP (ENGINE SPEED PULSE)

Outputs engine speed pulse

With engine running: pulses

26⁽¹⁾

PUR/WHT

VSSOUT (VEHICLE SPEED SENSOR OUTPUT SIGNAL)

Sends vehicle speed sensor signal

Depending on vehicle speed: pulses With ignition switch ON (II): battery voltage

LTGRN/BLK

IMOCD (IMMOBILIZER CODE)

Detects immobilizer signal

28⁽²⁾

BLU/WHT

ACS (A/C SWITCH SIGNAL)

Detects A/C switch signal

With A/C switch ON (II): about 0 V With A/C switch OFF: about 5.0 V

BRN

SCS (SERVICE CHECK SIGNAL)

Detects service check signal

With service check signal shorted using HDS: about 0 V
With service check signal open: about 5.0 V

RED/BLU

WEN (WRITE ENABLE SIGNAL)

Detects service enable signal

With ignition switch ON (II): about 0 V

⁽¹⁾

A/T

⁽²⁾

With A/C