CONTROL SYSTEM - Engine Control Unit Terminal Voltage Table

F-128spec table

Engine Control Unit Terminal Voltage (1A-1Q)

Terminal	Input	Output	Connection to	Test condition	Voltage	Remark
1A	—	—	Battery	Constant	Approx. 12V	For backup
1B	O		Main relay	Ignition switch OFF	Approx. 0V
1B	O		Main relay	Ignition switch ON	Approx. 12V
1C	O		Ignition switch (Start position)	While cranking	Approx. 10V
1C	O		Ignition switch (Start position)	Ignition switch ON	Approx. 0V
1D		O	Self-Diagnosis Checker (Monitor lamp)	Test switch at "SELF-TEST" Lamp illuminated for 3 sec. after ignition switch OFF→ON	Approx. 5V	With Self-Diagnosis Checker and System Selector
1D		O	Self-Diagnosis Checker (Monitor lamp)	Lamp not illuminated after 3 sec.	Approx. 12V	With Self-Diagnosis Checker and System Selector
1D		O	Self-Diagnosis Checker (Monitor lamp)	Test switch at "O₂ MONITOR" at idle Monitor lamp illuminated	Approx. 5V	With Self-Diagnosis Checker and System Selector
1D		O	Self-Diagnosis Checker (Monitor lamp)	Test switch at "O₂ MONITOR" at idle Monitor lamp not illuminated	Approx. 12V	With Self-Diagnosis Checker and System Selector
1E		O	Malfunction indicator lamp	Lamp illuminated for 3 sec. after ignition switch OFF→ON	Below 2.5V	With System Selector test switch at "SELF-TEST"
1E		O	Malfunction indicator lamp	Lamp not illuminated after 3 sec.	Approx. 12V	With System Selector test switch at "SELF-TEST"
1E		O	Malfunction indicator lamp	Lamp illuminated	Below 2.5V	With System Selector test switch at "SELF-TEST"
1F		O	Self-Diagnosis Checker (Code number)	Buzzer sound for 3 sec. after ignition switch OFF→ON	Below 2.5V	• With Self-Diagnosis Checker and System Selector • With System Selector test switch at "SELF-TEST"
1F		O	Self-Diagnosis Checker (Code number)	Buzzer not sounded after 3 sec.	Approx. 12V	• With Self-Diagnosis Checker and System Selector • With System Selector test switch at "SELF-TEST"
1F		O	Self-Diagnosis Checker (Code number)	Buzzer sounded	Below 2.5V	• With Self-Diagnosis Checker and System Selector • With System Selector test switch at "SELF-TEST"
1F		O	Self-Diagnosis Checker (Code number)	Buzzer not sounded	Approx. 12V	• With Self-Diagnosis Checker and System Selector • With System Selector test switch at "SELF-TEST"
1G		O	Igniter	Ignition switch ON	Approx. 0V
1G		O	Igniter	Idle	Approx. 0.2V
1H		O	Igniter	Ignition switch ON	Approx. 0V
1H		O	Igniter	Idle	Approx. 0.2V
1I	—	—	—	—	—	—
1J		O	A/C relay	Ignition switch ON	Approx. 12V
1J		O	A/C relay	A/C switch ON at idle	Below 2.5V
1J		O	A/C relay	A/C switch OFF at idle	Approx. 12V
1K	O		Diagnosis connector	System Selector test switch at "O₂ MONITOR"	Approx. 12V
1K	O		Diagnosis connector	System Selector test switch at "SELF-TEST"	Approx. 0V
1L	—	—	—	—	—	—
1M	—	—	—	—	—	—
1N	O		Throttle sensor (Idle point)	Accelerator pedal released	Approx. 0V	Ignition switch ON
1N	O		Throttle sensor (Idle point)	Accelerator pedal depressed	Approx. 12V	Ignition switch ON
1O	O		Stoplight switch	Brake pedal released	0V
1O	O		Stoplight switch	Brake pedal depressed	Approx. 12V
1P	O		P/S pressure switch	Ignition switch ON	Approx. 12V
1P	O		P/S pressure switch	P/S ON (at idle)	0V
1P	O		P/S pressure switch	P/S OFF (at idle)	Approx. 12V
1Q	O		A/C switch	A/C switch ON (Ignition switch ON)	Below 2.5V	Blower motor ON
1Q	O		A/C switch	A/C switch OFF (Ignition switch ON)	Approx. 12V

Input—

Output—

Connection toBattery

Test conditionConstant

VoltageApprox. 12V

RemarkFor backup

InputO

Output

Connection toMain relay

Test conditionIgnition switch OFF

VoltageApprox. 0V

Remark

InputO

Output

Connection toMain relay

Test conditionIgnition switch ON

VoltageApprox. 12V

Remark

InputO

Output

Connection toIgnition switch (Start position)

Test conditionWhile cranking

VoltageApprox. 10V

Remark

InputO

Output

Connection toIgnition switch (Start position)

Test conditionIgnition switch ON

VoltageApprox. 0V

Remark

Input

OutputO

Connection toSelf-Diagnosis Checker (Monitor lamp)

Test conditionTest switch at "SELF-TEST" Lamp illuminated for 3 sec. after ignition switch OFF→ON

VoltageApprox. 5V

RemarkWith Self-Diagnosis Checker and System Selector

Input

OutputO

Connection toSelf-Diagnosis Checker (Monitor lamp)

Test conditionLamp not illuminated after 3 sec.

VoltageApprox. 12V

RemarkWith Self-Diagnosis Checker and System Selector

Input

OutputO

Connection toSelf-Diagnosis Checker (Monitor lamp)

Test conditionTest switch at "O₂ MONITOR" at idle Monitor lamp illuminated

VoltageApprox. 5V

RemarkWith Self-Diagnosis Checker and System Selector

Input

OutputO

Connection toSelf-Diagnosis Checker (Monitor lamp)

Test conditionTest switch at "O₂ MONITOR" at idle Monitor lamp not illuminated

VoltageApprox. 12V

RemarkWith Self-Diagnosis Checker and System Selector

Input

OutputO

Connection toMalfunction indicator lamp

Test conditionLamp illuminated for 3 sec. after ignition switch OFF→ON

VoltageBelow 2.5V

RemarkWith System Selector test switch at "SELF-TEST"

Input

OutputO

Connection toMalfunction indicator lamp

Test conditionLamp not illuminated after 3 sec.

VoltageApprox. 12V

RemarkWith System Selector test switch at "SELF-TEST"

Input

OutputO

Connection toMalfunction indicator lamp

Test conditionLamp illuminated

VoltageBelow 2.5V

RemarkWith System Selector test switch at "SELF-TEST"

Input

OutputO

Connection toSelf-Diagnosis Checker (Code number)

Test conditionBuzzer sound for 3 sec. after ignition switch OFF→ON

VoltageBelow 2.5V

Remark• With Self-Diagnosis Checker and System Selector • With System Selector test switch at "SELF-TEST"

Input

OutputO

Connection toSelf-Diagnosis Checker (Code number)

Test conditionBuzzer not sounded after 3 sec.

VoltageApprox. 12V

Remark• With Self-Diagnosis Checker and System Selector • With System Selector test switch at "SELF-TEST"

Input

OutputO

Connection toSelf-Diagnosis Checker (Code number)

Test conditionBuzzer sounded

VoltageBelow 2.5V

Remark• With Self-Diagnosis Checker and System Selector • With System Selector test switch at "SELF-TEST"

Input

OutputO

Connection toSelf-Diagnosis Checker (Code number)

Test conditionBuzzer not sounded

VoltageApprox. 12V

Remark• With Self-Diagnosis Checker and System Selector • With System Selector test switch at "SELF-TEST"

Input

OutputO

Connection toIgniter

Test conditionIgnition switch ON

VoltageApprox. 0V

Remark

Input

OutputO

Connection toIgniter

Test conditionIdle

VoltageApprox. 0.2V

Remark

Input

OutputO

Connection toIgniter

Test conditionIgnition switch ON

VoltageApprox. 0V

Remark

Input

OutputO

Connection toIgniter

Test conditionIdle

VoltageApprox. 0.2V

Remark

Input—

Output—

Connection to—

Test condition—

Voltage—

Remark—

Input

OutputO

Connection toA/C relay

Test conditionIgnition switch ON

VoltageApprox. 12V

Remark

Input

OutputO

Connection toA/C relay

Test conditionA/C switch ON at idle

VoltageBelow 2.5V

Remark

Input

OutputO

Connection toA/C relay

Test conditionA/C switch OFF at idle

VoltageApprox. 12V

Remark

InputO

Output

Connection toDiagnosis connector

Test conditionSystem Selector test switch at "O₂ MONITOR"

VoltageApprox. 12V

Remark

InputO

Output

Connection toDiagnosis connector

Test conditionSystem Selector test switch at "SELF-TEST"

VoltageApprox. 0V

Remark

Input—

Output—

Connection to—

Test condition—

Voltage—

Remark—

Input—

Output—

Connection to—

Test condition—

Voltage—

Remark—

InputO

Output

Connection toThrottle sensor (Idle point)

Test conditionAccelerator pedal released

VoltageApprox. 0V

RemarkIgnition switch ON

InputO

Output

Connection toThrottle sensor (Idle point)

Test conditionAccelerator pedal depressed

VoltageApprox. 12V

RemarkIgnition switch ON

InputO

Output

Connection toStoplight switch

Test conditionBrake pedal released

Voltage0V

Remark

InputO

Output

Connection toStoplight switch

Test conditionBrake pedal depressed

VoltageApprox. 12V

Remark

InputO

Output

Connection toP/S pressure switch

Test conditionIgnition switch ON

VoltageApprox. 12V

Remark

InputO

Output

Connection toP/S pressure switch

Test conditionP/S ON (at idle)

Voltage0V

Remark

InputO

Output

Connection toP/S pressure switch

Test conditionP/S OFF (at idle)

VoltageApprox. 12V

Remark

InputO

Output

Connection toA/C switch

Test conditionA/C switch ON (Ignition switch ON)

VoltageBelow 2.5V

RemarkBlower motor ON

InputO

Output

Connection toA/C switch

Test conditionA/C switch OFF (Ignition switch ON)

VoltageApprox. 12V

Remark

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CONTROL SYSTEM - Engine Control Unit Terminal Voltage Table

Engine Control Unit Terminal Voltage (1A-1Q)

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