Engine 2 Data
ENGINE SPEED - Range 0-9999 RPMEngine speed is computed by the PCM from the 3X reference input. It should remain close to desired idle under various engine loads with engine idling.
DESIRED IDLE - Range 0-3187 RPM
The idle speed that is commanded by the PCM. The PCM will compensate for various engine loads based on engine coolant temperature to keep the engine at the desired speed.
ECT - Range -40°C to 151°C, -40°F to 304°F
The Engine Coolant Temperature (ECT) sensor is mounted in the coolant stream and sends engine temperature information to the PCM. 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 will decrease and the PCM will interpret the lower voltage as a warm engine.
IAT - Range -40°C to 151 °C, -40°F to 304°F
The PCM converts the resistance of the intake air temperature sensor to degrees. Intake Air Temperature (IAT) is used by the PCM to adjust fuel delivery and spark timing according to incoming air density.
IAC POSITION - Range 0-255
Displays the commanded position of the idle air control pintle in counts. A larger number of counts means that more air is being commanded through the idle air passage. Idle air control should respond fairly quickly to changes in engine load to maintain desired idle RPM.
IDLE SPEED ERROR - Range 0-12800 RPM
The displayed value is the difference between the PCM commanded idle speed (Desired Idle) and the actual Engine Speed.
BARO - Scan Tool Range 10-105 kPa/0.00-5.00 Volts
The Barometric Pressure reading is determined from the MAP sensor signal monitored during key up and Wide-Open Throttle (WOT) conditions. The Barometric Pressure is used to compensate for altitude differences.
MAP - Scan Tool Range 10-105 kPa/0.00-4.97 Volts
The Manifold Absolute Pressure (MAP) sensor measures the change in the intake manifold pressure from engine load, EGR flow, and speed changes. As intake manifold pressure increases, intake vacuum decreases resulting in a higher MAP sensor voltage and kPa reading. The MAP sensor signal is used to monitor intake manifold pressure changes during the EGR flow test, to update the BARO reading, and as an enabling factor for several of the diagnostics.
MAF - Scan Tool Range 0.0-512 gm/s
Mass Air Flow (MAF) is the MAF Input Frequency converted to grams of air per second. This indicates the amount of air entering the engine.
ENGINE RUN TIME - Scan Tool Range 00:00:00-99:99:99 Hrs:Min:Sec
Indicates the time elapsed since the engine was started. If the engine is stopped, ENGINE RUN TIME will be reset to 00:00:00.
CAM SIG PRESENT - Scan Tool Displays YES or NO
Indicates whether or not the correct CAM signal has been received by the PCM during the last six 3X Reference pulses. NO displayed indicates no CAM signal received. A toggling display indicates an intermittent CAM signal.
18X CRANK SENSOR - Scan Tool Range 0-1280 RPM
Displays the engine speed calculated from the 18X Reference signal PCM input. Should nearly match ENGINE SPEED up to 1280 RPM limit.
IGNITION MODE - Scan Tool Displays BYPASS or IC
Indicates the commanded state of the Bypass signal output from the PCM. When BYPASS is displayed the PCM allows the ignition control module to keep the spark advance at a fixed 10 BTDC. Ignition Control (IC) displayed indicates that the PCM has signaled the ignition module that the PCM is going to control the spark advance (IC mode). The ignition control module determines correct operating mode based on the level of voltage that the PCM sends to the ignition control module on the bypass circuit. The PCM provides 5 volts to the ignition control module if the PCM is going to control spark timing (IC mode). If the PCM does not turn "ON" the 5 volts, or if the ignition control module doesn't receive it, the module will keep control of spark timing (Bypass mode).
SPARK - Scan Tool Range -64 to 64
Displays the amount of spark advance being commanded by the PCM on the IC circuit. Because the ignition control module sets spark advance at a fixed value of 10 BTDC while operating in Bypass mode, the displayed Spark advance only reflects true spark timing when the PCM has commanded IC mode.
KS Noise Channel - Scan Tool Range 0.0-5.0 Volts
Indicates the current voltage level being monitored on the Knock Sensor (KS) noise channel. The PCM determines whether knock is occurring by comparing the signal level on the KS circuit with the voltage level on the noise channel. The noise channel allows the PCM to reject any false knock signal by indicating the amount of normal engine mechanical noise present. Normal engine noise varies depending on engine speed and load.
KS MINIMUM LEARNED NOISE - Scan Tool Range 0.0-5.0 Volts
Indicates the minimum level that the PCM has detected on the noise channel while the noise level was being learned. If a noise channel voltage is detected below the minimum learned noise, a problem is indicated.
KNOCK RETARD - Scan Tool Range 0.0-25.5
Indicates the amount of spark the PCM is removing from IC spark advance in response to the signal from the Knock sensors.
KS ACTIVITY - Scan Tool Displays YES or NO
"YES" displayed indicates that knock is being detected.
DESIRED EGR POS. - Scan Tool Range 0%-100%
Represents the EGR pintle position that the PCM is commanding. DESIRED EGR POS. should stay close to ACTUAL EGR POS.
ACTUAL EGR POS - Scan Tool Range 0%-100%
Represents the actual position of the EGR pintle in percent. 0% displayed indicates a fully extended pintle (EGR valve closed).
EVAP VACUUM SW. - Scan Tool Displays PURGE or NO PURGE
The EVAP purge vacuum switch is a normally closed switch positioned in the purge line between the canister and the EVAP purge solenoid. The EVAP purge vacuum switch will open when vacuum increases to greater than 5 inches of water in the purge line. The EVAP Purge Vacuum Switch is used by the PCM to monitor EVAP canister purge solenoid operation and purge system integrity. The EVAP Purge Vacuum Switch should be closed to ground with no vacuum present (0% EVAP Purge PWM). With EVAP Purge PWM at 25% or greater, the EVAP Purge Vacuum Switch should open and purge should be indicated.
EVAP PURGE PWM - Scan Tool Range 0%-100%
Represents the PCM commanded PWM duty cycle of the EVAP Purge Solenoid valve. 0% displayed indicates no purge; 100% displayed indicates full purge.
TRANS. HOT MODE - Scan Tool Displays ACTIVE or INACTIVE
ACTIVE displayed indicates that the PCM has detected conditions appropriate for transmission hot mode operation. The PCM determines this base on transmission fluid temperature. While in Hot Mode, transmission shift points may be altered, 4th gear disabled, and the TCC forced "ON" in 2nd gear.
COMMANDED TCC - Scan Tool Displays ENGAGED or DISENGAGED
Represents the PCM commanded state of the transmission torque converter clutch.
TRANS RANGE - Scan Tool Displays INVALID, PARK/NEUTRAL, REVERSE, DRIVE 4, DRIVE 3, DRIVE 2, or LOW
Trans Range represents the decoded status of the three transmission range pressure switch inputs from the Transmission Range Pressure Switch Assembly. The combination of transmission range inputs indicates the position of the transmission manual valve.
IGNITION 1 - Scan Tool Range 0-25.5 Volts
This represents the system voltage measured by the PCM at its ignition feed (CKT 439).
A/C REQUEST - Scan Tool Displays YES or NO
Indicates the state of the A/C request input circuit from the HVAC controls. The PCM uses the A/C request signal to determine whether A/C compressor operation is being requested.
COMMANDED A/C - Scan Tool Displays ON or OFF
Represents the PCM commanded state of the A/C compressor clutch relay driver circuit. The A/C compressor clutch should be engaged when Commanded A/C displays ON.
A/C SLUGGING - Scan Tool Displays ACTIVE or INACTIVE
ACTIVE displayed indicates that the PCM is engaging the A/C compressor clutch at start-up to avoid A/C slugging when A/C is requested.
A/C PRESSURE - Scan Tool Displays 0.00-5.00 Volts
Represents the A/C refrigerant pressure sensor signal. The amount of pressure indicates the amount of load that the A/C compressor is placing on the engine. The PCM uses this information to adjust idle and to control the cooling fans.
A/C PRESSURE OUT OF RANGE - Scan Tool Displays YES or NO
YES displayed indicates that the PCM is monitoring an A/C Refrigerant Pressure signal voltage which is too high or too low to allow the A/C compressor clutch to engage.
A/C OFF FOR WOT - Scan Tool Displays YES or NO
YES displayed indicates that the PCM has commanded the A/C compressor clutch relay OFF because the throttle position is above the threshold for A/C compressor operation (TP Angle greater than 90%).
TP ANGLE - Scan Tool Range 0-100%
TP Angle is computed by the PCM from the TP sensor voltage. TP Angle should display 0% at idle and 100% at wide open throttle.
COMMANDED FAN 1 - Scan Tool Displays ON or OFF/COMMANDED FAN 2
Scan Tool Displays ON or OFF - Represents the PCM commanded state of the FAN 1 and FAN 2 relay drivers.
VEHICLE SPEED - Scan Tool Range 0-255 km/h, 0-155 mph
The vehicle speed sensor signal is converted into km/h and mph for display.
ENGINE LOAD - Scan Tool Range 0%-100%
Engine load is calculated by the PCM from engine speed and MAF sensor readings. Engine Load should increase with an increase in RPM or airflow.
TWC PROTECTION - Scan Tool Displays ACTIVE or INACTIVE
ACTIVE displayed indicates that the PCM has detected conditions appropriate to operate in TWC Protection mode. This is determined based on Engine Load and Engine Coolant Temperature. While in TWC Protection. the PCM will decrease Air/Fuel Ratio to a value that depends on Mass Air Flow (higher Mass Airflow = lower Air/Fuel Ratio).
HOT OPEN LOOP - Scan Tool Displays ACTIVE or INACTIVE
ACTIVE displayed indicates that the PCM has detected conditions appropriate to operate in Hot Open Loop mode. The PCM determines this based on Engine Coolant Temperature, Mass Air Flow and Vehicle Speed. While in Hot Open Loop, the PCM ignores inputs from the exhaust oxygen sensors and bases fuel delivery on Throttle Position, Engine Coolant Temperature, and Mass Air Flow.
DECEL FUEL MODE - Scan Tool Displays ACTIVE or INACTIVE
ACTIVE displayed indicates that the PCM has detected conditions appropriate to operate in Deceleration Fuel mode. The PCM will command deceleration fuel mode when a sudden decrease in throttle position has been detected while the vehicle is traveling over 20 mph. While in Deceleration Fuel mode, the PCM will decrease the amount of fuel delivered by entering Open Loop and decreasing the injector pulse width.
POWER ENRICHMENT - Scan Tool Displays ACTIVE or INACTIVE
ACTIVE displayed indicates that the PCM has detected conditions appropriate to operate in Power Enrichment mode. The PCM will command Power Enrichment mode when a large increase in throttle position and load is detected. While in Power Enrichment, the PCM will increase the amount of fuel delivered by entering Open Loop and increasing the injector pulse width. This is done to prevent a possible sag or hesitation from occurring during acceleration.