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For 1990-2009 cars only

Data Display

The scan tool displays the module data. This information assists in determining whether the module is operating properly, and whether the module is sending or receiving the proper data to and from a particular system. The module uses data received from other systems in order to carry out some functions. If the module receives the incorrect data from another system, the module may function improperly. Use the scan tool in order to review the data from the systems that interact with the module.

Displayed Input/Output Status

The scan tool also displays the module input/output status. Select the module input/output status display in order to display the data and determine if the switched inputs/outputs may be properly interpreted. The display also indicates if the input/output has changed states. For example, when a door is closed, the scan tool displays the input status of the door ajar switch as INACTIVE. When the door is open, the scan tool reads ACTIVE. Use this type of information when diagnosing a malfunction associated with a particular module input or an input that is shared with another system.

Control Outputs

Use a scan tool in order to control the module output functions. When the module output control is selected, the scan tool can command the module to turn an output on or off. This feature may be used in order to determine if the module is able to control an output regardless of the inputs or any specific program instructions. Once a test is selected, the scan tool will command the module to energize the selected output. The scan tool then displays the status of the selected output. The displayed information represents only what was module commanded, not what action was actually taken. Verify that the module is performing each of the selected output functions.

Scan Tool Menus

Refer to the Scan Tool Manual for complete information on scan tool diagnostics.

Diagnostic Trouble Codes (DTC)

The diagnostic trouble codes (DTC) function has the following 3 modes:

DTC Information: Current or history DTCs stored by the EBTCM may be displayed.

DTC History: Displays the conditions under which a history DTC was set.

Clear DTC Information: Current or history DTCs stored by the EBTCM may be cleared.

Data Display (1) Diagnostics

The data display (1) diagnostics function has the following 4 modes:

    • CONTROLLER INFORMATION 1
    • CONTROLLER INFORMATION 2
    • DATA DISPLAY 1
    • DATA DISPLAY 2

A brief description of data display (1) diagnostics parameters available on the scan tool are listed below:

CONTROLLER INFORMATION 1:

System ID: Scan tool displays: hexadecimal - Display indicates the system ID.

Controller Part Number: Scan tool displays: part number - Display indicates the part number of the EBTCM.

Build Sequence Number: Scan tool displays: number - Display indicates the number in order that the EBTCM was built.

Julian Date of Build: Scan tool displays: day/year - Display indicates the day and year which the EBTCM was built.

ABS Controller: Scan tool displays: Yes/No - Display indicates if the vehicle is equipped with ABS.

TCS Controller: Scan tool displays: Yes/No - Display indicates if the vehicle is equipped with TCS.

ICCS2/3: Scan tool displays: Yes/No - Display indicates if the vehicle is equipped with ICCS2/3.

Electronic Brake Lining Wear: Scan tool displays: Yes/No - Displays indicates state of wear in the brake lining.

Magna Steer Controller: Scan tool displays: Yes/No - Display indicates if the vehicle is equipped with Magna Steer®.

CONTROLLER INFORMATION 2:

ROM Part Number: Scan tool displays: part number - Display indicates the ROM part number of the EBTCM.

End Model Part Number: Scan tool displays: part number - Display indicates the end model part number of the EBTCM.

Calibration Part Number: Scan tool displays: part number - Display indicates the calibration part number of the EBTCM.

DATA LIST 1:

Vehicle Speed: Scan tool displays: Km/h or mph - Display indicates vehicle speed from the average of all four wheel speeds.

LF Wheel Speed: Scan tool displays: Km/h or mph - Display indicates the actual speed of the left front wheel.

RF Wheel Speed: Scan tool displays: Km/h or mph - Display indicates the actual speed of the right front wheel.

LR Wheel Speed: Scan tool displays: Km/h or mph - Display indicates the actual speed of the left rear wheel.

RR Wheel Speed: Scan tool displays: Km/h or mph - Display indicates the actual speed of the right rear wheel.

Rough Road Parameter: Scan tool displays: G - Display indicates the EBTCM calculation of the road surface, this information is sent to the PCM over the class 2 serial data line. The PCM uses this information for misfire detection.

RR Inlet Solenoid: Scan tool displays: Inactive/Active - Display indicates the state of the solenoid valve.

RR Outlet Solenoid: Scan tool displays: Inactive/Active - Display indicates the state of the solenoid valve.

LR Inlet Solenoid: Scan tool displays: Inactive/Active - Display indicates the state of the solenoid valve.

LR Outlet Solenoid: Scan tool displays: Inactive/Active - Display indicates the state of the solenoid valve.

RF Inlet Solenoid: Scan tool displays: Inactive/Active - Display indicates the state of the solenoid valve.

RF Outlet Solenoid: Scan tool displays: Inactive/Active - Display indicates the state of the solenoid valve.

LF Inlet Solenoid: Scan tool displays: Inactive/Active - Display indicates the state of the solenoid valve.

LF Outlet Solenoid: Scan tool displays: Inactive/Active - Display indicates the state of the solenoid valve.

LF TCS Prime Valve: Scan tool displays: Inactive/Active - Display indicates the state of the solenoid valve.

LF TCS Isolation Valve: Scan tool displays: Inactive/Active - Display indicates the state of the solenoid valve.

RF TCS Prime Valve: Scan tool displays: Inactive/Active - Display indicates the state of the solenoid valve.

RF TCS Isolation Valve: Scan tool displays: Inactive/Active - Display indicates the state of the solenoid valve.

DATA LIST 2:

Brake Light Switch: Scan tool displays: Applied/Released - Display indicates the state of the brake switch.

Extended Travel Brake Switch: Scan tool displays: Applied/Released - Display indicates the state of the brake switch.

ABS Active: Scan tool displays: Yes/No - Display indicates if ABS is currently active.

ABS Failed: Scan tool displays: Yes/No - Display indicates if ABS is inactive do to a malfunction.

ABS Warning Lamp: Scan tool displays: Off/On - Display indicates if ABS Warning Lamp is currently active.

TCS Active: Scan tool displays: Yes/No - Display indicates if TCS is currently active.

TCS Active Message: Scan tool displays: Off/On - Display indicates if TCS Active Message is currently being displayed on the DIC.

TCS Failed: Scan tool displays: Yes/No - Display indicates if TCS is inactive do to a malfunction.

TCS Disabled Message: Scan tool displays: Off/On - Display indicates if TCS Disabled Message is currently being displayed on the DIC.

TCS Warning Lamp: Scan tool displays: Off/On - Display indicates if TCS Warning Lamp is currently active.

Requested Torque: Scan tool displays: Percent - Display indicates how much torque the EBTCM is requesting the PCM to deliver.

Delivered Torque: Scan tool displays: Percent - Display indicates how much torque the PCM is delivering.

Brake Temp Status (Thermal Model Cutoff): Scan tool displays: Yes/No - Display indicates if the brake temperature is above the thermal cutoff.

Brake Lining Wear Input Status: Scan tool displays: Low/High - Display indicates the state of wear in the brake lining.

LF Rotor Temp: Scan tool displays: °C/°F - Display indicates the estimated temperature of the brake rotor.

RF Rotor Temp: Scan tool displays: °C/°F - Display indicates the estimated temperature of the brake rotor.

Lateral Accelerometer Input: Scan tool displays: Volts - Display indicates the lateral accelerometer signal from the lateral accelerometer, roughly 2.5 volts equals 0 lateral acceleration.

Yaw Rate Sensor Input: Scan tool displays: Volts - Display indicates the yaw signal from the yaw rate sensor, roughly 2.5 volts equals 0 yaw.

Stabilitrak Steering Angle Is Centered: Scan tool displays: Yes/No - Display indicates if the steering wheel is centered.

Stabilitrak Active: Scan tool displays: Yes/No - Display indicates if Stabilitrak is currently active.

Stabilitrak Active Message: Scan tool displays: Off/On - Display indicates if Stabilitrak Active Message is currently being displayed on the DIC.

Stabilitrak Failed: Scan tool displays: Yes/No - Display indicates if Stabilitrak is inactive do to a malfunction.

Stabilitrak Failed Message: Scan tool displays: Off/On - Display indicates if Stabilitrak Failed Message is currently being displayed on the DIC.

ICCS2 Data Link Left: Scan tool displays: Percent - Display indicates the normal force duty cycle sent by the CVRSS.

ICCS2 Data Link Right: Scan tool displays: Percent - Display indicates the normal force duty cycle sent by the CVRSS.

Magna Steer Failed: Scan tool displays: Yes/No - Display indicates if Magna Steer® is inactive due to a malfunction.

Magna Steer Commanded Current: Scan tool displays: amps - Display indicates the amount of current the EBTCM is commanding to the Magna Steer® actuator.

Magna Steer Feedback Current: Scan tool displays: amps - Display indicates the actual current that was sent to the Magna Steer® actuator.

Analog Steering Wheel Position: Scan tool displays: Volts - Display indicates the position of the Steering Wheel Position Sensor by displaying the analog voltage, roughly 2.5 volts when the front wheels are pointed straight.

Digital SWPS Phase A: Scan tool displays: High/Low - Display indicates the state of the Phase A pulse. The EBTCM uses the state change from Phase A and Phase B to calculate the position of the front wheels. The EBTCM also determines the direction the front wheels are rotating. If Phase A changes state first the wheels are turning left, if Phase B changes state first the wheels are turning right.

Digital SWPS Phase B: Scan tool displays: High/Low - Display indicates the state of the Phase B pulse. The EBTCM uses the state change from Phase A and Phase B to calculate the position of the front wheels. The EBTCM can also determine the direction the front wheels are rotating. If Phase A changes state first the wheels are turning left, if Phase B changes state first the wheels are turning right.

Ignition Power: Scan tool displays: Volts - Display indicates the level of ignition voltage at the EBTCM.

Switched System Battery Power: Scan tool displays: Volts - Display indicates the voltage available to the solenoid valves and the pump motor control relay coil when the solenoid valve control relay is energized.

Switched Pump Battery Power: Scan tool displays: Volts - Display indicates the voltage available to the pump motor when the pump motor control relay is energized.

Solenoid Relay Commanded State: Scan tool displays: On/Off - Display indicates the commanded state of the valve relay.

Solenoid Relay Feedback State: Scan tool displays: On/Off - Display indicates the state of the valve relay.

Motor Relay Commanded State: Scan tool displays: On/Off - Display indicates the commanded state of the valve relay.

Motor Relay Feedback State: Scan tool displays: On/Off - Display indicates the state of the valve relay.

Data Display (2) Normal Mode

The Data Display (2) Normal Mode parameters available on the scan tool are listed below:

Brake Switch - ABS Input: Scan tool displays: Applied/Released - Display indicates the state of the brake switch as seen by the EBTCM.

Brake Switch - PCM Input: Scan tool displays: Applied/Released - Display indicates the state of the brake switch as seen by the PCM.

Brake Travel Switch - PCM Input: Scan tool displays: Applied/Released - Display indicates the state of the extended brake travel switch.

ABS Failed Lamp Command: Scan tool displays: Yes/No - Display indicates if the ABS Failed Lamp has been commanded to be on.

Traction Control Equipped: Scan tool displays: Yes/No - Display indicates if Traction Control is equipped.

Traction Engaged Message Command: Scan tool displays: Yes/No - Display indicates if the Traction Engaged Message has been commanded to be on.

Traction Suspended Message Command: Scan tool displays: Yes/No - Display indicates if the Traction Suspended Message has been commanded to be on.

Traction Off Message Command: Scan tool displays: Yes/No - Display indicates if the Traction Off Message has been commanded to be on.

Traction Ready Message Command: Scan tool displays: Yes/No - Display indicates if the Traction Ready Message has been commanded to be on.

Temporary Inhibit of TCS: Scan tool displays: Yes/No - Display indicates if TCS has been temporarily inhibited.

Powertrain TCS Failure: Scan tool displays: Yes/No - Display indicates if TCS is inactive due to a powertrain malfunction.

Suspension System Failure: Scan tool displays: Yes/No - Display indicates if the suspension system is inactive due to a malfunction.

Service Steering Message Command: Scan tool displays: Yes/No - Display indicates if the Service Steering Message has been commanded to be on.

Service Stability System: Scan tool displays: Yes/No - Display indicates if the Stability system should be serviced.

Stability System Engaged: Scan tool displays: Yes/No - Display indicates if the stability system has engaged.

Service Stability Message Command: Scan tool displays: Yes/No - Display indicates if the Service Stability Message has been commanded to be on.

Snapshot

In this test mode, the scan tool captures the data listed in the data displays before and after a snapshot-triggering condition which may or may not set a DTC.

Special Functions

In this test mode, the scan tool may be used in order to perform functional tests on the system which help verify proper operation. Malfunction conditions may be further identified by testing and observing the test results. You must clear any DTCs before any tests in Special Functions may be performed. The Special Functions are grouped in the following manner:

    • Solenoid Test
    • Automated Bleed
    • Automated Test
    • Lamp/Message(s) Test
    • TCS Test
    • ICCS2 Data Link Test
    • Steering Position Sensor Test

The Special Functions are detailed below.

Solenoid Test-Pressure Hold

This test activates the selected wheel circuit inlet valve, placing the valve in the pressure hold position. When the valve is in the pressure hold position, the valve will not allow master cylinder pressure to be delivered to the hydraulic wheel circuit. This is done under actual operating conditions when the EBTCM determines that the wheel is moving too slowly. The EBTCM holds additional master cylinder pressure from the hydraulic wheel circuit in an attempt to allow the circuit to rotate at an appropriate speed. The scan tool commands the valve to close. This should allow the technician to spin the wheel even though an assistant is applying pressure to the brake pedal. Perform the following test:

  1. Turn OFF the ignition.
  2. Connect a scan tool to the data link connector (DLC).
  3. Turn ON the ignition, with the engine OFF.
  4. Raise the vehicle. Ensure that all of the wheels are about 15 cm (6 in) off of the floor.
  5. Place the gear selector in the NEUTRAL position.
  6. Select the Special Functions from the ABS/TCS/ICCS menu.
  7. Select the Solenoid Test. Have an assistant command Inlet Valve Solenoid of the appropriate wheel using the scan tool.
  8. Have the assistant press and hold the brake pedal.
  9. Attempt to move the wheel being tested by hand. The wheel should move even though the assistant is applying pressure to the brake pedal. The front wheels may be difficult to turn by hand, but may be moved if the system is working properly.

Solenoid Test-Pressure Release

This test activates the selected hydraulic wheel circuit outlet valves, placing them in the pressure reduce position. When in the pressure reduce position, the valve will allow wheel caliper pressure to be returned to the master cylinder circuit. This is done under actual operating conditions because the EBTCM has determined that the wheel is moving too slowly, and holding additional master cylinder pressure from it has not allowed it to rotate at an appropriate speed. The scan tool commands the valves to these positions which should allow the technician to spin the wheel even though an assistant is applying pressure to the brake pedal. Perform the following test:

  1. Turn OFF the ignition.
  2. Connect a scan tool to the data link connector (DLC).
  3. Turn ON the ignition, with the engine OFF.
  4. Raise the vehicle. Ensure that all of the wheels are about 15 cm (6 in) off of the floor.
  5. Place the gear selector in the NEUTRAL position.
  6. Select the Special Functions from the ABS/TCS/ICCS menu.
  7. Select the Solenoid Test. Have an assistant command the Outlet Valve Solenoid of the appropriate wheel using the scan tool.
  8. Have the assistant press and hold the brake pedal.
  9. Attempt to move the wheel being tested by hand. The wheel should move even though the assistant is applying pressure to the brake pedal. The front wheels may be difficult to turn by hand, but may be moved if the system is working properly.

Automated Bleed

The Automated Bleed mode of the scan tool is used during bleeding of the ABS System. Refer to Antilock Brake System Automated Bleed Procedure .

Automated Test

This test cycles each valve solenoid and the pump motor (as well as the necessary relays) in order to verify component operation. This test is identical to the Initialization Sequence. If a malfunction is detected, the EBTCM will set DTCs. The DTCs will be displayed upon completion of the test. Perform the following test:

  1. Turn OFF the ignition.
  2. Connect a scan tool to the data link connector (DLC).
  3. Turn ON the ignition, with the engine OFF.
  4. Select the Special Functions from the ABS/TCS/ICCS menu.
  5. Select the Automated Test.
  6. Run the Automated Test.
  7. Record any DTCs that were set.

Lamp/Message(s) Test

This test controls the following indicator lamps and DIC messages:

    • TCS INDICATOR LAMP
    • ABS INDICATOR LAMP
    • TRACTION ENGAGED MESSAGE
    • SERVICE STABILITY SYSTEM MESSAGE
    • STABILITY ENGAGED MESSAGE

TCS Test

This test runs the pump motor in order to apply fluid pressure to the front wheel circuits.

Perform the following test. This test does NOT require an assistant:

  1. Turn OFF the ignition.
  2. Connect a scan tool to the data link connector (DLC).
  3. Turn ON the ignition, with the engine OFF.
  4. Raise the vehicle. Ensure that all of the wheels are about 15 cm (6 in) off of the floor.
  5. Select the Special Functions from the ABS/TCS/ICCS menu.
  6. Select the TCS Test.
  7. Command the TCS Test ON with the scan tool. The pump motor will turn on for approximately 25 seconds.
  8. Attempt to move each front wheel by hand. The wheels should not move due to the pump motor running and applying pressure to the front wheels.

ICCS2 Data Link Test

This test ensures that the wires are not crossed between the EBTCM and the CVRSS module. The 2 choices under ICCS2 Data Link Test are the ICCS2 Data Link Left and the ICCS2 Data Link Right. The ICCS2 Data Link Test first tests for any EBTCM or CVRSS DTC(s). If any EBTCM or CVRSS codes are set, then this test will not run. If the test is successful, the scan tool will display a test complete message. If the wires are crossed and this test is run, the scan tool will display an electrical malfunction message.

Steering Position Sensor Test

This test monitors the analog and digital steering angle position. Perform the following test only after the steering wheel position sensor (SWPS) has been centered:

  1. Turn OFF the ignition.
  2. Connect a scan tool to the data link connector (DLC).
  3. Turn the ignition switch to the ON position (start the engine).
  4. Place the steering wheel in the center position.
  5. Monitor the Stabilitrak Steering Angle Is Centered in the ABS/TCS/ICCS Data Display (1) Diagnostics, DATA LIST 2. The scan tool will indicate Yes with the steering wheel centered.
  6. Drive the vehicle in a straight line for 45 seconds at 24 Km/h (15 mph) while monitoring the scan tool.
  7. Stop the vehicle and leave the engine running.
  8. Select the Special Functions from the ABS/TCS/ICCS menu.
  9. Select the Steering Position Sensor Test.
  10. While monitoring the test on the scan tool, fully turn the steering wheel to the left, then fully turn the steering wheel to the right (lock to lock) 3 times.
  11. Read the scan tool each time the wheels are straight and the steering wheel is at the center position. This reading should always be near zero for the digital and analog display (± 5 degrees of each other).