Part 2

Scan Tool Data Definitions - Continued

HO2S Bank 1 Sensor 1
- A YES display indicates that the oxygen sensor is warmed up and is capable of sending useful voltage readings to the PCM. A NO display indicates a cold (not ready) oxygen sensor.
Indicates the status of the fuel control exhaust oxygen sensor. The scan tool will indicate that the exhaust oxygen sensors are ready when the PCM detects a fluctuating heated oxygen sensor (HO2S) voltage sufficient to allow closed loop operation. This will not occur unless the exhaust oxygen sensors are warmed up.

HO2S Bank 1 Sensor 1 Ready
- A YES display indicates that the oxygen sensor is warmed up and is capable of sending useful voltage readings to the PCM. A NO display indicates a cold (not ready) oxygen sensor.
Indicates the status of the fuel control exhaust oxygen sensor. The scan tool will indicate that the exhaust oxygen sensors are ready when the PCM detects a fluctuating HO2S voltage sufficient to allow closed loop operation. This will not occur unless the exhaust oxygen sensors are warmed up.

HO2S Bank 1 Sensor 2
- The scan tool displays mV.
The scan tool displays a range of 0-1,106 mV. The HO2S bank 2 sensor 2 parameter represents the exhaust oxygen sensor output voltage. The voltage fluctuates constantly within a range between 10 mV, and 1,000 mV, while operating in Closed Loop.
The scan tool displays 0 to 1275 mV. This parameter is the actual voltage on the HO2S signal circuit as measured by the ECM.

HO2S Bank 1 Sensor 2 Ready
- A YES display indicates that the oxygen sensor is warmed up and is capable of sending useful voltage readings to the PCM. A NO display indicates a cold (not ready) oxygen sensor.
Indicates the status of the post catalyst oxygen sensor. The scan tool will indicate that the exhaust oxygen sensors are ready when the PCM detects a fluctuating HO2S voltage.

HO2S Bank 2 Sensor 1
- This parameter indicates the HO2S bank 1 sensor 1 output voltage as measured by the control module. The scan tool value fluctuates constantly while operating in Closed Loop. The scan tool will display a higher value during rich running conditions, and a lower value during leaner running conditions.

HO2S Bank 2 Sensor 1 Ready
- A YES display indicates that the oxygen sensor is warmed up and is capable of sending useful voltage readings to the PCM. A NO display indicates a cold (not ready) oxygen sensor.
Indicates the status of the post catalyst oxygen sensor. The scan tool will indicate that the exhaust oxygen sensors are ready when the PCM detects a fluctuating HO2S voltage.

HO2S Bank 2 Sensor 2
- This parameter indicates the HO2S bank 1 sensor 2 output voltage as measured by the control module. The scan tool will display a higher value during rich running conditions, and a lower value during leaner running conditions.
The post-catalyst HO2S output voltage will fluctuate slowly over a longer period of time, compared to the fuel control oxygen sensor s. This is due to the oxygen storage capacity of an efficiently operating catalyst.
The scan tool displays 0 to 1275 mV. This parameter is the actual voltage on the HO2S signal circuit as measured by the control module.

HO2S Heater Bn 1 Sensor 1 Command
- This parameter displays the commanded state of the heater control circuit for oxygen bank 1 sensor 1. The oxygen sensor heater should be on when the scan tool indicates the HO2S Heater Command is On. The oxygen sensor heater should be off when the scan tool indicates the HO2S Heater Command is Off.

HO2S Heater Bn 1 Sensor 2 Command
- This parameter displays the commanded state of the heater control circuit for oxygen bank 1 sensor 2. The oxygen sensor heater should be on when the scan tool indicates the HO2S Heater Command is On. The oxygen sensor heater should be off when the scan tool indicates the HO2S Heater Command is Off.

HO2S Heater Bn 2 Sensor 1 Command
- This parameter displays the commanded state of the heater control circuit for oxygen bank 2 sensor 1. The oxygen sensor heater should be on when the scan tool indicates the HO2S Heater Command is On. The oxygen sensor heater should be off when the scan tool indicates the HO2S Heater Command is Off.

HO2S Heater Bn 2 Sensor 2 Command
- This parameter displays the commanded state of the heater control circuit for oxygen bank 2 sensor 2. The oxygen sensor heater should be on when the scan tool indicates the HO2S Heater Command is On. The oxygen sensor heater should be off when the scan tool indicates the HO2S Heater Command is Off.

HO2S Heater Bn 1 Sen. 1
- This parameter displays the current through the control module when the bank 1 sensor 1 HO2S heater is commanded ON by the control module. HO2S Heater Bn 1 Sen. 1 is a range of values indicating a low current when the heater circuit resistance is high to a high current when the heater circuit resistance is low.

HO2S Heater Bn 1 Sen. 2
- This parameter displays the current through the control module when the bank 1 sensor 2 HO2S heater is commanded ON by the control module. HO2S Heater Bn 1 Sen. 2 is a range of values indicating a low current when the heater circuit resistance is high to a high current when the heater circuit resistance is low.

HO2S Heater Bn 2 Sen. 1
- This parameter displays the current through the control module when the bank 2 sensor 1 HO2S heater is commanded ON by the control module. HO2S Heater Bn 2 Sen. 1 is a range of values indicating a low current when the heater circuit resistance is high to a high current when the heater circuit resistance is low.

HO2S Heater Bn 2 Sen. 2
- This parameter displays the current through the control module when the bank 2 sensor 2 HO2S heater is commanded ON by the control module. HO2S Heater Bn 2 Sen. 2 is a range of values indicating a low current when the heater circuit resistance is high to a high current when the heater circuit resistance is low.

HO2S Heater Bn 1 Sen. 1 Circuit History
- This parameter displays the diagnostic state of the output driver for the HO2S Heater Bn 1 Sen. 1. The scan tool will display OK if the circuit is operating correctly. The scan tool will display Fault if there is an open, short to ground or a short to voltage on the circuit.

HO2S Heater Bn 1 Sen. 2 Circuit History
- This parameter displays the diagnostic state of the output driver for the HO2S Heater Bn 1 Sen. 2. The scan tool will display OK if the circuit is operating correctly. The scan tool will display Fault if there is an open, short to ground or a short to voltage on the circuit.

HO2S Heater Bn 2 Sen. 1 Circuit History
- This parameter displays the diagnostic state of the output driver for the HO2S Heater Bn 2 Sen. 1. The scan tool will display OK if the circuit is operating correctly. The scan tool will display Fault if there is an open, short to ground or a short to voltage on the circuit.

HO2S Heater Bn 2 Sen. 2 Circuit History
- This parameter displays the diagnostic state of the output driver for the HO2S Heater Bn 2 Sen. 2. The scan tool will display OK if the circuit is operating correctly. The scan tool will display Fault if there is an open, short to ground or a short to voltage on the circuit.

HO2S Heater Bn 1 Sen. 1 Circuit Status
- This parameter displays the status of the output driver for the HO2S Heater Bn 1 Sen. 1. The scan tool will display OK if the circuit is operating correctly. The scan tool will display Fault if there is an open, short to ground or a short to voltage on the circuit.

HO2S Heater Bn 1 Sen. 2 Circuit Status
- This parameter displays the status of the output driver for the HO2S Heater Bn 1 Sen. 2. The scan tool will display OK if the circuit is operating correctly. The scan tool will display Fault if there is an open, short to ground or a short to voltage on the circuit.

HO2S Heater Bn 2 Sen. 1 Circuit Status
- This parameter displays the status of the output driver for the HO2S Heater Bn 2 Sen. 1. The scan tool will display OK if the circuit is operating correctly. The scan tool will display Fault if there is an open, short to ground or a short to voltage on the circuit.

HO2S Heater Bn 2 Sen. 2 Circuit Status
- This parameter displays the status of the output driver for the HO2S Heater Bn 2 Sen. 2. The scan tool will display OK if the circuit is operating correctly. The scan tool will display Fault if there is an open, short to ground or a short to voltage on the circuit.

IAT Sensor
- The scan tool displays °C.
The PCM converts the resistance of the intake air temperature (IAT) sensor to degrees in the same manner as the engine coolant temperature (ECT) sensor. Intake air temp is used by the PCM to adjust fuel delivery and spark timing according to incoming air density.
The scan tool displays a range of -39 to +140°C (-38 to +284°F). The PCM converts the resistance of the intake air temperature sensor to degrees. The PCM uses the IAT in order to adjust fuel delivery and spark timing according to incoming air density.

Ignition 1 Signal
- This parameter displays the voltage measured at the ignition 1 circuit of the control module. Voltage is applied to the control module when the ignition switch is in the ignition 1 position.

Ignition Off Time
- The Scan tool displays time in minutes.
This parameter is used by the control module to identify the amount of time that has passed. This parameter is used for various components and systems including throttle actuator control (TAC) system and the EVAP system.

Initial Brake Apply Signal
- The Scan tool displays Release and Applied.
This parameter indicates when the brake pedal is initially depressed.

Injector PWM
- The scan tool displays mS
Indicates the base PWM or ON time of the fuel injectors in milliseconds. When the engine load is increased, the injector pulse width will increase.
Indicates the amount of time the PCM is commanding each injector ON during each engine cycle. A longer injector pulse width will cause more fuel to be delivered. Injector pulse width should increase with increased engine load.

Knock Retard
- The scan tool displays °.
Indicates the amount of spark the PCM is removing from ignition control (IC) spark advance in response to the signal from the knock sensors. The traction control system desired torque signal from the electronic brake and traction control module (EBTCM) may cause knock retard to display a value more than 0.0 degrees if traction control is active.

Long Term FT Bank 1
- The scan tool range is -99 to +99 percent. This parameter indicates the Long Term fuel trim (FT) correction for bank 1 as commanded by the PCM.
A change made to the fuel delivery will be indicated by the Long and Short Term FT values. The Short Term FT values change rapidly in response to the HO2S signal voltages. These changes fine tune the engine fueling. The Long Term FT values change in response to the trends in the Short Term FT. The Long Term FT makes coarse adjustments to the fueling in order to re-center and restore control to the Short Term FT. The Short Term FT and the Long Term FT can be monitored with a scan tool. A positive fuel trim value indicates that the ECM is adding fuel in order to compensate for a lean condition. A negative fuel trim value indicates that the ECM is reducing the amount of fuel in order to compensate for a rich condition.

Long Term FT Bank 2
- The scan tool range is -99 to 99 percent. This parameter indicates the Long Term FT correction for bank 2 as commanded by the PCM.
A change made to the fuel delivery will be indicated by the Long and Short Term FT values. The Short Term FT values change rapidly in response to the HO2S signal voltages. These changes fine tune the engine fueling. The Long Term FT values change in response to the trends in the Short Term FT. The Long Term FT makes coarse adjustments to the fueling in order to re-center and restore control to the Short Term FT. The Short Term FT and the Long Term FT can be monitored with a scan tool. A positive fuel trim value indicates that the ECM is adding fuel in order to compensate for a lean condition. A negative fuel trim value indicates that the ECM is reducing the amount of fuel in order to compensate for a rich condition.

Loop Status
- Closed loop indicates that the PCM is controlling fuel delivery according to oxygen sensor voltage. In open loop, the PCM ignores the oxygen sensor voltage and bases the amount of fuel to be delivered on throttle position (TP) sensor, ECT, and MAF sensor inputs only.