Electric Load Sensor: Testing and Inspection

Electrical load signals (component "ON") are sent to the ECU from the headlight switch, blower motor switch, cooling fan switches and rear window defroster switch.

HEADLIGHT SWITCH

Headlight switch signal can be checked at ECU terminal 1H. With headlights "ON," terminal voltage should be approximately 12V. With headlights "OFF," voltage should be below 1.5V.

BLOWER MOTOR SWITCH

Blower motor switch signal can be checked at ECU terminal 1P, ignition "ON." With blower switch "OFF" or in low position, terminal voltage should be approximately 12V. With switch "ON" in 3rd or 4th high position, voltage should be below 1.5V.

COOLING FAN SWITCHES

NO. 1 SWITCH (LOW)

Fan switch signal can be checked at ECU terminal 2D. With coolant temperature below 97°C (207°F), terminal should read battery voltage. Above 97°C (207°F), voltage should be below 1.5V.

NO. 2 SWITCH (HIGH, AUTO. TRANS.)

Fan switch signal can be checked at ECU terminal 2G. With coolant temperature below 108°C (226°F), terminal should read battery voltage. Above 108°C (226°F), voltage should be below 1.5V.

REAR WINDOW DEFROSTER SWITCH

Rear window defroster switch signal can be checked at ECU terminal 1J, ignition "ON." With defroster switch "OFF," terminal should read battery voltage. With switch "ON," voltage should be below 1.5V.