For 1990-2009 cars only
Scan Tool Data Definitions Disengage History
One of the following conditions must be present in order for a disengagement parameter to appear:
| • | The Cruise Control System is active and disengagement is requested. |
| • | The engagement of the Cruise Control System is requested while a fault is present. |
APP Override: The ECM detects that the accelerator pedal overrides the set vehicle speed for approximately 60 seconds.
Brake: The ECM detects that the stop lamps have been activated according to the brake pedal position (BPP) sensor / stop lamp switch input from the platform module. Also, the brake pedal being applied according to the brake fluid pressure sensor input can also set this disengagement reason with vehicles equipped with the vehicle stability enhancement system (VSES).
BPP Data: The ECM detects an invalid brake pedal apply serial data message from the platform module.
BPP DTC: The ECM detects that DTC P0703 is active.
Cancel: The ECM detects that the cruise control cancel switch has been activated.
Clutch: The ECM detects that the clutch pedal switch has been activated.
Coast Disengage: When the ECM detects that the cruise set/coast signal is active and the throttle blade fully closes the cruise control system will disengage until the ECM detects that the set/coast signal is inactive. The cruise control system will then engage and set with the new vehicle speed.
Coast Speed Low: The ECM detects that the Set/Coast switch is activated until the vehicle speed is below 37 km/h (23 mph).
Cruise S/W: The ECM detects that a cruise control software execution error is present.
Cruise Sw Data: A fault in the serial data circuit from the cruise control switch to the platform module is detected.
Cruise Sw. Off: The ECM detects that the cruise On/Off switch was turned to OFF when the cruise control system was enabled.
D Whl Spd Low: The ECM detects the driven wheels are at a slower speed than the non-driven wheels.
D Whl Spd Hi: The ECM detects the driven wheels are at a faster speed than the non-driven wheels.
Decel Rate: The ECM detects that the vehicle deceleration is greater than the calibrated cruise control threshold.
DLC Override: The ECM detects that a DLC override has occurred.
DTC Set: The ECM detects that a DTC has been set which affects the cruise control operation.
ECM Inhibit: The ECM detects a RAM corruption associated to the cruise control system.
ECT Overtemp: The ECM detects the engine temperature is above the calibrated threshold.
Engine Run Time: The ECM detects that the cruise control system has been requested and the engine run time counter is not active.
Engine Speed: The ECM detects that the engine speed is less than or greater than a calibrated RPM.
First Gear: While the cruise control system is active, the ECM detects that the transmission is in Drive 1.
High Speed: The ECM detects that the vehicle speed is greater than the calibrated amount.
High Voltage: The ECM detects that the ignition voltage is above 16 volts.
Illegal Mode: The ECM detects that the acceleration mode is active without the activation of the Accel. switch.
Lost Fwd Gear: The ECM detects that transmission is in Neutral, Reverse or Park.
Low Speed: The ECM detects that the vehicle speed is less than 37 km/h (23 mph) while the cruise control system was enabled.
Low Voltage: The ECM detects that the ignition voltage is below 9 volts.
Memory DTC: The ECM detects an internal memory fault.
MPH Limit: The ECM detects the vehicle is over speed and that the fuel shutoff has been activated.
None: This parameter is displayed when a new ECM has been installed.
Over Set Speed: The ECM detects the current vehicle speed is greater than the set vehicle speed by more than a calibrated amount.
Park Brake: ECM detects the park brake switch is active.
Pedal Initialize: The ECM detects that a stop lamp pedal activation had not occurred before the cruise control system was requested.
PTO Active: The ECM detects power take off is active.
RPM Limit: The ECM detects the engine is over speed and that the fuel shutoff has been activated.
S/C On - Speed High: The ECM detects 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.
Simul SC/RA Sw: The ECM detects that the Set/Coast switch and the Resume/Accel switch are active at the same time.
Sw Invalid: The ECM detects the analog cruise control switch input is out of the normal voltage range.
TAC Inhibit: The ECM detects a fault within the throttle actuator control (TAC) system.
TCS: The 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.
Trans. DTC: The ECM detects a transmission gear fault.
Under Set Speed: The ECM detects that the vehicle speed is less than the cruise memory speed by more than a calibrated amount.
VSES: The ECM detects that the vehicle stability enhancement system had been activated.
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.
APP Indicated Angle: This parameter displays the angle of the accelerator pedal as calculated by the control module using the signals from the accelerator pedal position sensors. The accelerator pedal position (APP) indicated angle is a range of values indicating a low percentage when the accelerator pedal is not depressed to a high percentage when the accelerator pedal is fully depressed.BPP Circuit Signal: The scan tool displays Applied or Released. This is the state of the brake pedal position (BPP) sensor as received by the engine control module (ECM) from the body control module (BCM) via a GMLAN serial data message.
BPP Signal: The scan tool displays Applied, Released or Invalid. This is the state of the BPP sensor as received by the ECM from the BCM via a GMLAN serial data message.
Cruise Cancel Switch: The scan tool displays Active, Inactive or Invalid. This is the state of the cruise cancel switch as received by the ECM from the BCM via a GMLAN serial data message.
Cruise Control Active: The scan tool displays Active, Inactive or Invalid. This is the state of the cruise control system as detected by the ECM.
Cruise Control Switch: The scan tool displays On, Off, Resume, Set, Error or Cancel. This is the status of the cruise control switch as detected by the BCM.
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 (Disengaged History) for descriptions.
Cruise On/Off Switch: The scan tool displays On or Off. The ECM receives a GMLAN serial data message from the BCM indicating the status of the cruise on/off switch. The BCM monitors the cruise control set/coast and resume/accelerate switch signal circuit. A closed switch is displayed as On.
Cruise Resume/Accel. Switch: The scan tool displays On or Off. The ECM receives a GMLAN serial data message from the BCM indicating the status of the cruise resume/accel switch. The BCM monitors the cruise control set/coast and resume/accelerate switch signal circuit. A closed switch is displayed as On. The cruise control On/Off switch must be switched On in order to correctly view the Cruise Resume/Accel. Switch parameter.
Cruise Set/Coast Switch: The scan tool displays On or Off. The ECM receives a GMLAN serial data message from the BCM indicating the status of the cruise set/coast switch. The BCM monitors the cruise control set/coast and resume/accelerate switch signal circuit. A closed switch is displayed as On. The cruise control On/Off switch must be switched On in order to correctly view the Cruise Set/Coast Switch parameter.
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.
Engine Speed: The scan tool displays 0 to 9,999 RPM. The ECM monitors the CKP signal circuit in order to determine the engine RPM.
Ignition 1 Signal: The scan tool displays 6 volts to 18 volts. The ECM monitors the Ignition 1 signal circuit in order to determine the system voltage.
TP Desired Angle: This parameter indicates the TP angle commanded by the control module. The scan tool will display a low value at idle, and a high value at wide open throttle (WOT).
TP Indicated Angle: This parameter displays the angel of the throttle position (TP) in percent. This information is calculated by the control module using the signals from the throttle position sensors. The scan tool will display a low percentage when the throttle plates are closed. The scan tool will display a high percentage when the throttle plates are fully open.
Vehicle Speed Sensor: The scan tool displays 0 to 150 km/h (93.2 mph). The ECM monitors the vehicle speed sensor signal circuit in order to calculate the vehicle speed for display.
