Actron KAL9615 - Manual (Page 32)

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COOLANT (°F) (Engine Coolant Temperature - PCM input)
COOLANT (°C)
Display: Numeric temperature value: -40 to 419 (°F) or -40 to 215 (°C).
This is a measure of the engine’s coolant temperature. A voltage signal is sent to
the PCM from a sensor that is in contact with the coolant. The voltage signal in-
creases as temperature increases. The PCM converts this voltage reading to a
degree measurement.
The PCM uses coolant temperature to help determine correct air/fuel ratios, spark
advance, idle speed, and emission device operation depending on the engine’s
temperature. Coolant temperature is also used to decide whether to run the engine
in open or closed loop mode.
The coolant parameter may be displayed in English or Metric, depending upon the
tool setup.
ENGINE (RPM) (Engine Speed in Revolutions Per Minute - PCM input)
Display: 0 to (maximum RPM)
This signal is sent from a triggering device (usually on the crankshaft or in the
distributor) to the PCM indicating engine speed.
Engine speed measurements can be used in the calculation on fuel injector pulse
widths and other powertrain operating strategies.
FUEL PRES (PSIG) (Fuel Pressure - PCM input)
FUEL PRES (KPA)
Display: 0 - 110 (psig) or 0 - 765 (kPa)
Fuel pressure is a measurement of the fuel rail (regulated) pressure. A sensor
sends the PCM an electrical signal which is converted to psig or kPa depending
upon English or Metric tool setup.
FUEL SYSTEM 1 (Fuel System Bank 1/2 - PCM calculated value)
FUEL SYSTEM 2
Display: OPEN, CLSD, OPEN1, OPEN2, CLSD1
The fuel system PIDs show the loop status of the fuel system banks. If the vehicle
calibration only uses one loop status for the fuel system the FUEL SYSTEM 1 PID will
be used.
There are four states the fuel system can be running in:
1. OPEN PCM is operating in the Open Loop control strategy. The vehicle has not yet
satisfied conditions for the PCM to go closed loop.
2. CLSD PCM currently functioning in Closed loop control strategy, using O2
sensor(s) as feedback for fuel control
3. OPEN1 Open Loop control strategy is being used by the PCM due to driving
conditions. Driving conditions that may cause this to happen are power
enrichment and deceleration enrichment.
4. OPEN2 The PCM is operating in Open Loop control strategy due to detected
system fault. Certain actuator or sensor faults will cause the PCM to use
an open loop strategy.
5. CLSD1 Closed Loop control is current storage being used by the PCM, but a fault
with at least one O2 sensor has been detected. The control system may
be using single O2 for fuel control calculations.