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Scan Tool Data Definitions



Scan Tool Data Definitions

Ambient Air Temp Sensor
- The scan tool displays voltage. This is the ambient air temperature sensor voltage as monitored by the body control module (BCM). The BCM converts the sensor voltage to a temperature value and sends the information via GMLAN serial data circuit to the instrument panel cluster (IPC) for display.

Battery Voltage Signal
- The scan tool displays 0-19 V. This is the voltage measured at the battery positive voltage circuit of the BCM.

Battery Voltage Signal
- The scan tool displays 0-19 V. This is the voltage measured at the battery positive voltage circuit of the IPC.

Brake Fluid Level Sensor
- The scan tool displays Ok or Low. This is the status of the brake fluid level sensor as monitored by the BCM.

Chime
- The scan tool displays On or Off. This is the state of the vehicle chime function as commanded by the IPC.

Cruise Control Active
- The scan tool displays Yes or No. This is state of the cruise control switch signal as monitored by the engine control module (ECM)/powertrain control module (PCM).

DIC Information Switch
- The scan tool displays Inactive or Active. This is the state of the driver information center (DIC) information switch as monitored by the IPC. The DIC switches are hardwired to and read by the IPC.

DIC Switch
- The scan tool displays Clear/Menu/Info/Reset. This is the DIC switch inputs as monitored by the BCM via GMLAN serial data. The BCM is responsible for driving DIC displays via GMLAN.

DIC Switch Input
- The scan tool displays voltage. This is the DIC switch input as monitored by the IPC.

Door Ajar Switch
- The scan tool displays Door Ajar/Door Closed. This the state of the door ajar switch as monitored by the BCM.

Driver Door Ajar Switch
- The scan tool displays Door Closed or Door Ajar. This is the state of the driver door ajar switch as monitored by the BCM. The driver door ajar switch is hardwired to and read by the BCM.

ECT Sensor
- The scan tool displays -40 to +151°C (-40 to +304°F). The ECM/PCM monitors the voltage at the signal circuit of the engine coolant temperature sensor. The voltage is inversely proportional to the engine coolant temperature.

Engine Oil Level Switch
- The scan tool displays Ok or Low. This is the state of the engine oil level switch as monitored by the ECM. The ECM receives the engine oil level data via a GMLAN serial data message.

Engine Oil Life Remaining
- The scan tool displays 100-0%. The scan tool displays the engine oil life remaining as monitored and calculated by the ECM/PCM.

Engine Oil Pressure Switch
- The scan tool displays Ok or Low. This is the status of the engine oil pressure switch signal as monitored by the ECM/PCM.

Engine Oil Temperature Calculated
- The scan tool displays Fahrenheit (Celsius). This is the status of the engine oil temperature as calculated by the ECM.

Engine Speed
- The scan tool displays 0-8000 RPM. The engine speed is computed by the ECM/PCM from the ignition reference input. It should remain close to the desired idle under various engine loads.

Fuel Level Sensor
- The scan tool displays 0-5 volts. The ECM/PCM monitors the signal circuit of the fuel level sensor and the fuel data is sent via the GMLAN to the IPC for display.

Fuel Tank Level Remaining
- The scan tool displays 0-100%. The ECM/PCM calculates the amount of fuel remaining in the tank based on the input from the fuel level sensor signal circuit.

Headlamp Off Switch
- The scan tool displays Off or On. This is the status of the headlamp-off switch as monitored by the BCM.

Headlamp On Switch
- The scan tool displays Off or On. This is the status of the headlamp-on switch as monitored by the BCM.

Ignition 1 input
- The scan tool displays Active or Inactive. The scan tool displays Active when voltage is present at the ignition 1 input of the IPC.

Ignition 1 Signal
- The scan tool displays 9-16 V. This is the voltage present at the ignition 1 voltage circuit of the ECM/PCM.

Ignition Accessory Signal
- The scan tool displays On or Off. The scan tool displays On when voltage is present at the ignition accessory signal circuit.

Key In Ignition Cylinder Switch
- The scan tool displays Yes or No. This is the status of the key-in-ignition cylinder switch as monitored by the BCM. When the key is in the ignition cylinder, the scan tool displays On.

Menu Switch
- The scan tool displays Off or On. This is the status of the DIC menu switch as monitored by the IPC.

MIL Command
- The scan tool displays Off or On. This is the commanded state of the malfunction indicator lamp (MIL) by the ECM/PCM. The MIL should be On in the IPC when scan tool displays MIL Command is On.

Non-Driven Wheel Speed
- The scan tool displays 0-255 km/h (0-155 mph). This is the vehicle non-driven wheel speed as monitored by the ECM.

Odometer
- The scan tools displays kilometers or miles. The scan tool displays the current mileage of the vehicle in kilometers or miles. The odometer is stored in the BCM and transmitted over GMLAN serial data to the IPC for display.

Park Lamp Switch
- The scan tool displays Off or On. This is the status of the park lamp switch as monitored by the BCM.

Reduced Engine Power
- The scan tool displays Active or Inactive. This is the state of the Reduced Engine Power indicator as commanded by the ECM/PCM.

Reset Switch
- The scan tool displays Active or Inactive. This is the status of the DIC reset switch as monitored by the IPC.

Trunk Ajar Switch
- The scan tool display Trunk Closed or Trunk Ajar. This is the status of the trunk ajar switch as monitored by the BCM.

Trunk Release Switch
- The scan tool displays Active/Inactive. This is the status of the trunk release switch as monitored by the BCM.

Vehicle Speed Sensor
- The scan tool displays 0-255 km/h (0-155 mph). This is the vehicle speed as calculated by the ECM/PCM.