ECT: The scan tool displays -40°C to +151°C (-40°F to +304°F).
The Engine Coolant Temperature (ECT) sensor is mounted in the coolant
stream. The PCM applies 5 volts to the ECT sensor circuit.
The sensor is a thermistor which changes internal resistance as
temperature changes. When the sensor is cold (internal
resistance high), the PCM monitors a high signal voltage
and interprets it as a cold engine. As the sensor warms (internal
resistance decreases), the voltage signal decreases and
the PCM interprets the lower voltage as a warm engine.
Engine Hot Lamp: The scan tool displays On or Off. This parameter indicates the
state of the indicator lamp.
Engine Hot Lamp Circuit Status: The scan tool displays OK or Fault. This parameter indicates the
state of the driver circuit for this device.
Engine Hot Lamp Command: The scan tool displays On or Off. This parameter indicates the
state of the indicator lamp.
Fans High Speed: The scan tool displays On or Off. The PCM is commanding all three
fan control relays on when the scan tool indicates On. When all fan control
relays are activated, both cooling fans are enabled on high
speed.
Fans Low Speed: The scan tool displays On or Off. The PCM is commanding Fan Control
relay 1 On when the scan tool indicates On. When the PCM commands the Fan
Control relay 1 On, both fans are enabled on low speed.
FC Relay 1: The scan tool displays OK or Fault. This parameter indicates the
state of the driver circuit for this device.
FC Relay 1 Circuit Status: The scan tool displays OK or Fault. This parameter indicates the
state of the driver circuit for this device.
FC Relay 1 Command: The scan tool displays On or Off. This parameter indicates the
state of the low speed fan relay driver.
FC Relay 2 and 3: The scan tool displays OK or Fault. This parameter indicates the
state of the driver circuit for this device.
FC Relay 2 and 3 Circuit Status: The scan tool displays OK or Fault. This parameter indicates the
state of the driver circuit for this device.
FC Relay 2 and 3 Command: The scan tool displays On or Off. This parameter indicates the
state of the high speed fan relay driver.