Scan Tool Data Definitions

ABS Lamp: The scan tool displays On/Off. The requested state of the ABS indicator as commanded by the Electronic Brake Control Module (EBCM). The BCM receives a class 2 message from the EBCM The IPC receives the illumination request from the BCM via the Serial Peripheral Interface (SPI).

Brake Warning Lamp: The scan tool displays On/Off. The requested state of the brake indicator as commanded by the BCM or the Electronic Brake Control Module (EBCM). The BCM receives a class 2 message from the EBCM. The IPC receives the illumination request from the BCM via the Serial Peripheral Interface (SPI).

Cruise Lamp: The scan tool displays On/Off. The requested state of the cruise indicator as commanded by the PCM. The BCM receives a class 2 message from the PCM. The IPC receives the illumination request from the PCM via the Serial Peripheral Interface (SPI).

Division: The scan tool displays Chevrolet/Invalid. The IPC transmits the division to the BCM via the Serial Peripheral Interface (SPI).

Door Ajar Lamp: The scan tool displays On/Off. The requested state of the door ajar indicator as commanded by the BCM.

ECT Sensor: The scan tool displays -4O-151°C (-4-304°F). The 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/Low. The PCM monitors the signal circuit of the engine oil level switch, where an open switch is displayed as Low (low engine oil level).

Engine Oil Pressure Switch: The scan tool displays OK/Low. The PCM monitors the signal circuit of the engine oil pressure switch, where a closed switch is displayed as Low (low engine oil pressure). Engine Speed: The scan tool displays 0-9999 RPM. Engine speed is computed by the PCM from the 3X reference input. It should remain close to desired idle under various engine loads with the engine idling.

English/Metric State: The scan tool displays English Units/Metric. The current unit of measurement used by the IPC.

Fuel Gage Position: The scan tool displays 0-255 counts. The BCM converts the fuel level percent class 2 message from the PCM into a gage position. The IPC receives the fuel gage position message from the BCM via the Serial Peripheral Interface (SPI).

Fuel Tank Level Remaining: The scan tool displays 0-100%. The PCM calculates the amount of fuel remaining in the tank based on the input from the fuel level sensor. The BCM receives a class 2 message from the PCM indicating the fuel level percent.

Gear Position: The scan tool displays Drive/Drive 1/Drive 2/Drive 3/Neutral/Reverse/Park. The BCM displays the gear position as determined by the PCM.

Generator Lamp: The scan tool displays On/Off. The requested state of the charging system indicator as commanded by the PCM. The BCM receives a class 2 message from the PCM requesting illumination.

HI Beam Lamp: The scan tool displays On/Off. The requested state of the high beam indicator as commanded by the BCM.

High Coolant Temp Lamp: The scan tool displays On/Off. The requested state of the engine coolant temperature indicator as commanded by the PCM. The BCM receives a class 2 message from the PCM requesting illumination.

Key In Ignition: The scan tool displays Yes/No. The BCM monitors the ignition key alarm switch, where a closed switch is displayed as Yes (key is in the ignition).

Low Coolant Lamp: The scan tool displays On/Off. The requested state of the low engine coolant indicator as commanded by the BCM.

Low Fuel Lamp: The scan displays On/Off. The requested state of the low fuel indicator as commanded by the BCM. The BCM determines when the low fuel indicator should illuminate based on the fuel level percent class 2 message from the PCM.

Low Oil Lamp: The scan tool displays On/Off. The requested state of the engine oil level indicator as commanded by the PCM. The BCM receives a class 2 message from the PCM requesting illumination.

Low Washer Lamp: The scan tool displays On/Off. The requested state of the low washer fluid indicator as commanded by the BCM.

Oil Pressure Lamp: The scan tool displays On/Off. The requested state of the engine oil pressure indicator as commanded by the PCM. The BCM receives a class 2 message from the PCM requesting illumination.

Perk Lamp Input: The scan tool displays On/Off. The BCM monitors the headlamp switch, where a closed switch (park or head position) is displayed as On.

Phase Lock Loop: The scan tool displays OK/Fault. The timing state of the Serial Peripheral Interface (SPI).

Seat Belt Lamp: The scan tool displays On/Off. The requested state of the fasten safety belt indicator as commanded by the BCM.

Service Veh. Soon Lamp: The scan tool displays On/Off. The requested state of the service vehicle soon indicator as commanded by the BCM or PCM. The BCM receives a class 2 message from the PCM requesting illumination.

SPI Data Input: The scan tool displays High/Low. The state of the SPI serial data in circuit. The IPC transmits data to the BCM on this circuit.

SPI Data Output: The scan tool displays High/Low. The state of the SPI serial data out circuit. The BCM transmits data to the IPC on this circuit.

SPI Serial Data Status: The scan tool displays OK/Fault. That status of the Serial Peripheral Interface (SPI).

Tech Signal: The scan tool displays Active/Inactive. The IPC monitors the voltage at the engine speed signal circuit (converted output from the PCM). The IPC sends a message to the BCM via the Serial Peripheral Interface (SPI) indicating the status of the engine speed signal circuit.

Temp. Gage Position: The scan tool displays 0-255 counts. The BCM converts the engine coolant temperature class 2 message from the PCM into a gage position. The IPC receives the engine coolant temperature gage position message from the BCM via the Serial Peripheral Interface (SPI).

Theft System Lamp: The scan tool displays On/Off. The requested state of the theft system indicator as commanded by the BCM.

VSS Signal: The scan tool displays Active/Inactive. The IPC monitors the voltage at the vehicle speed signal circuit (converted output from the PCM). The IPC sends a message to the BCM via the Serial Peripheral Interface (SPI) indicating the status of the vehicle speed signal circuit.

Vehicle Speed Sensor: The scan tool displays 0-255 km/h (0-155 mph). The PCM monitors the voltage at the signal circuit of the vehicle speed sensor. The voltage is proportional to the vehicle speed.