Scan Tool Data Definitions Disengage History

The Cruise Control Scan Tool Definitions - Disengage History is a common list for all of the available cruise control disengagement definitions available on the scan tool. The cruise control system equipped on the vehicle determines which cruise control disengagement parameters are available on the scan tool.

One of the following conditions must be present in order for a disengagement parameter to appear:

Accel Rate: The powertrain control module (PCM)/engine control module (ECM) detects that the vehicle acceleration is greater than the calibrated cruise control threshold.

Bad Sequence: The PCM/ECM detects that a cruise control software execution error is present.

Brake: The PCM/ECM detects that the stop lamps have been activated or the PCM/ECM detects that a stop lamp pedal activation had not occurred before the cruise control system was requested.

Cancel: The PCM/ECM detects that the cruise control cancel switch has been activated.

CC Sw. Position: The PCM/ECM detects that the acceleration mode is active without the activation of the Accel. switch.

Clutch: The PCM/ECM detects that the clutch pedal switch has been activated.

Clutch Switch: The PCM/ECM detects that the clutch pedal switch has been activated.

Cruise Off: The PCM/ECM detects that the cruise On/Off switch was turned to OFF when the cruise control system was enabled.

Coast Low Speed: The PCM/ECM detects that the Set/Coast switch is activated until the vehicle speed is below 37 km/h (23 mph).

Coast Disengage: When the PCM/ECM detects that the cruise set/coast signal is active and the throttle blade fully closes the cruise control system will disengage until the PCM/ECM detects that the set/coast signal is inactive. The cruise control system will then engage and set with the new vehicle speed.

Decel Rate: The PCM/ECM detects that the vehicle deceleration is greater than the calibrated cruise control threshold.

DTC Set: The PCM/ECM detects that a DTC has been set which affects the cruise control operation.

Engine Run Time: The PCM/ECM detects that the cruise control system has been requested and the engine run time counter is not active.

Engine Speed: The PCM/ECM detects that the engine speed is less than or greater than a calibrated RPM.

ETC: The PCM/ECM detects a fault within the throttle actuator control (TAC) system.

First Gear: While the cruise control system is active, the PCM/ECM detects that the transmission is in Drive 1.

High Accel.: The PCM/ECM detects that the vehicle acceleration is greater than the calibrated cruise control threshold.

High Decel.: The PCM/ECM detects that the vehicle deceleration is greater than the calibrated cruise control threshold.

High Speed: The PCM/ECM detects that the vehicle speed is greater than the calibrated amount.

Illegal Mode: The PCM/ECM detects that the acceleration mode is active without the activation of the Accel. switch.

Injector Disable: The PCM/ECM detects that the engine is overspeed and that the fuel shutoff has been activated.

Low Speed: The PCM/ECM detects that the vehicle speed is less than 37 km/h (23 mph) while the cruise control system was enabled.

Low Voltage: The PCM/ECM detects that the ignition voltage is below 9 volts.

Manual/Neutral: The PCM/ECM detects that transmission is in Neutral, Reverse or Park.

Memory Corrupt: An internal PCM/ECM memory fault is detected.

MPH Limit: The PCM/ECM detects a that the vehicle is overspeed and that the fuel shutoff has been activated.

No History: This parameter is displayed when a new PCM/ECM has been installed.

None: This parameter is displayed when a new PCM/ECM has been installed.

Off: The PCM/ECM detects that the cruise On/Off switch was turned to OFF when the cruise control system was enabled.

Over Set Speed: This parameter is displayed when the current vehicle speed is greater than the set vehicle speed by more than a calibrated amount.

Over Speed: This parameter is displayed when the current vehicle speed is greater than the set vehicle speed by more than a calibrated amount.

Over Speed Tap: This parameter is displayed when the Set/Coast switch is briefly applied while the current vehicle speed is greater than the set vehicle speed by more than a calibrated amount.

Pedal Initialize: The PCM/ECM detects that a stop lamp pedal activation had not occurred before the cruise control system was requested.

PCM Error: The PCM/ECM detects that a cruise control software execution error is present.

PCM Inhibit: The PCM/ECM detects a RAM corruption associated to the cruise control system.

Pedal > Cruise: The PCM/ECM detects that the accelerator pedal overrides the set vehicle speed for approximately 60 seconds.

Serial Data: A fault in the serial data circuit from the cruise control switch to the platform module is detected.

S/C On, CC Off: When the PCM/ECM detects that the cruise set/coast signal is active and the throttle blade fully closes the cruise control system will disengage until the PCM/ECM detects that the set/coast signal is inactive. The cruise control system will then engage and set with the new vehicle speed.

S/C On - Speed High: This parameter is displayed when the Set/Coast switch is briefly applied while the current vehicle speed is greater than the set vehicle speed by more than a calibrated amount.

Stop Lamp Switch: The PCM/ECM detects that the stop lamps have been activated.

TAC Inhibit: The PCM/ECM detects a fault within the TAC system.

Traction: The PCM/ECM detects that the traction control system had been activated. It is also possible that a tire with low air pressure can also set this disengagement reason.

Traction Loss: The PCM/ECM detects that the traction control system had been activated. It is also possible that a tire with low air pressure can also set this disengagement reason.

Two Commands: The PCM/ECM detects that the Set/Coast switch and the Resume/Accel switch are active at the same time.

Two CC Commands: The PCM/ECM detects that the Set/Coast switch and the Resume/Accel switch are active at the same time.

Under Speed: The PCM/ECM detects that the vehicle speed is less than the cruise memory speed by more than a calibrated amount.

Under Set Speed: The PCM/ECM detects that the vehicle speed is less than the cruise memory speed by more than a calibrated amount.

Scan Tool Data Definitions Cruise Control

The Scan Tool Data Definitions contains a brief description of all cruise control related parameters available on the scan tool. On vehicles equipped with a 3.5L (LX9) engine, a powertrain control module (PCM) is used. On vehicles equipped with a 2.4L (LE5) or a 3.9L (LZ9) engine, an engine control module (ECM) is used.

Battery Voltage Signal: The scan tool displays 6-18 Volts. The powertrain control module (PCM) monitors the ignition voltage.

BPP Circuit Signal: The scan tool displays Applied or Released.

CPP Switch (If Equipped): The scan tool displays Applied or Released.

Cruise Cancel Switch: The scan tool displays Active or Inactive.

Cruise Control Active: The scan tool displays Active or Inactive. The ECM determines the current status of the cruise control operation. An operating cruise control system is displayed as Active.

Cruise Control Active: The scan tool displays Yes or No. The PCM determines the current status of the cruise control operation. An operating cruise control system is displayed as Yes.

Cruise Control Switch: The scan tool displays Off/On/Error/Resume/Set. The body control module (BCM) monitors the cruise control set/coast and resume/accel switch signal circuit in order to determine the status of the cruise control switch.

Cruise Control Switch: The scan tool displays 0-5 Volts. The BCM monitors the voltage of the cruise control set/coast and resume/accel switch signal circuit in order to determine the status of the cruise control switch. The list values are voltage values from a known good cruise control switch. Off = 0.0 Volts/On = 0.6 Volts/Resume = 1.5 Volts/Set = 3.0 Volts.

Cruise Disengage (1-6) History: The scan tool displays the last 6 reasons why the cruise control system was disengaged. Refer to the Scan Tool Data Definitions (Disengage History) for descriptions.

Cruise Disengage (1-8) History: The scan tool displays the last 8 reasons why the cruise control system was disengaged. Refer to the Scan Tool Data Definitions (Disengage History) for descriptions.

Cruise On/Off Switch: The scan tool displays On or Off. This is the state of the cruise control On/Off switch as detected by the ECM/PCM. An active switch is displayed as On.

Cruise Resume/Accel Switch: The scan tool displays Active or Inactive. This is the state of the resume/accel switch as detected by the ECM. An active cruise resume/accel switch is displayed as Active.

Cruise Resume/Accel Switch: The scan tool displays On or Off. This is the state of the resume/accel switch as detected by the PCM. An active cruise resume/accel switch is displayed as On.

Cruise Set/Coast Switch: The scan tool displays Active or Inactive. This is the state of the cruise set switch as detected by the PCM. An active cruise set switch is displayed as Active. The cruise control On/Off switch must be On in order to view the parameter correctly.

Cruise Set/Coast Switch: The scan tool displays On or Off. This is the state of the cruise set switch as detected by the PCM. An active cruise set switch is displayed as On. The cruise control On/Off switch must be On in order to view the parameter correctly.

Engine Speed: The scan tool displays 0 to 9999 RPM. This is the engine RPM as monitored by the ECM/PCM. The ECM/PCM monitors the crankshaft position (CKP) signal circuit in order to determine the engine RPM.

Ext. Travel BPP Signal: The scan tool displays Applied/Released.

Ignition 1 Signal: The scan tool displays 0 to 25.5 Volts. The ECM/PCM monitors the voltage of the ignition 1 voltage circuit.

Initial Brake Apply Signal: The scan tool displays Applied or Released. The BCM monitors the signal circuit of the brake pedal position sensor. When the PCM receives a GMLAN serial data message from the BCM indicating that the brake pedal has been applied, the scan tool displays Applied.

Reduced Engine Power: The scan tool displays Active or Inactive. When the PCM detects that a reduced engine power condition exists, the scan tool displays Active.

Stop Lamp Pedal Switch: The scan tool displays Applied or Released. The PCM monitors the stop lamp pedal switch signal circuit. An activated brake pedal is displayed as Applied.

Stop Lamp Pedal Switch Signal: The scan tool displays Volts. The PCM monitors the voltage of the stop lamp pedal switch signal circuit.

TAC/PCM Communication Signal: The scan tool displays OK or Fault. The PCM uses the universal asynchronous receiver transmitter (UART) serial data circuit in order to communicate with the throttle actuator control (TAC) module. A malfunction in the UART serial data circuit is displayed as Fault.

TAC Stop Lamp Pedal Switch: The scan tool displays Applied or Released. The TAC module monitors the stop lamp pedal switch signal circuit. An activated brake pedal is displayed as Applied.

TAC Vehicle Speed Signal: The scan tool displays OK or Fault. The TAC module monitors the vehicle speed signal circuit. A malfunction in the vehicle speed signal circuit is displayed as Fault.

Traction Control Status: The scan tool displays Active or Inactive. When the PCM detects that a traction control condition exists, the scan tool displays Active.

Vehicle Speed Circuit History: The scan tool displays OK/Open/Short/Invalid State. The PCM detects and determines the history of the vehicle speed circuit.

Vehicle Speed Circuit Status: The scan tool displays OK/Open/Short. When the PCM detects that a malfunction in the vehicle speed signal circuit exists, the scan tool will display Fault or Invalid State.

Vehicle Speed Sensor: The scan tool displays 0-255 km/h (0-155 mph). The ECM/PCM monitors the vehicle speed sensor signal in order to calculate the vehicle speed for display.