GM Service Manual Online
For 1990-2009 cars only

Scan Tool Output Control

Additional Menu Selections

Description

Refer to the scan tool manual for complete scan tool operating instructions.

ABS Motor

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This function allows the technician to command the ABS pump motor On and Off.

Exhaust Brake Control

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This function allows the technician to disable the exhaust brake control relay. When the Off key is pressed, the EBCM opens the ground circuit of the relay.

Lamp Tests

    • Service Brake Soon Lamp
    • Low Traction Lamp
    • Traction Off Lamp

This function allows the technician to command the service brake soon indicator, low traction indicator or the traction off indicator On and Off.

Solenoid Tests

    • Left Front Isolation Valve
    • Left Front Dump Valve
    • Right Front Isolation Valve
    • Right Front Dump Valve
    • Left Rear Isolation Valve
    • Left Rear Dump Valve
    • Right Rear Isolation Valve
    • Right Rear DumpValve

This function allows the technician to command a selected valve solenoid On and Off. Use the procedures below to verify proper operation of the EBCM and BPMV.

Dump Valve Solenoid Test Procedure

  1. Apply the parking brake fully.
  2. Start the engine and allow the engine to idle.
  3. Select the desired Dump Valve Solenoid Test on the scan tool.
  4. Apply the brake and maintain steady pressure on the brake pedal.
  5. Command the solenoid On and verify that the brake pedal drops to the floor.

Isolation Valve Solenoid Test Procedure

  1. Apply the parking brake fully.
  2. Start the engine and allow the engine to idle.
  3. Select the desired Isolation Valve Solenoid Test on the scan tool.
  4. Apply the brake with very light pressure only enough to close the brake switch.
  5. Command the solenoid On and then immediately apply firm and steady pressure to the brake pedal.
  6. The EBCM automatically de-energizes the solenoid after about 3 seconds. When this occurs, verify that the brake pedal drops about 2.2 cm (1 inch).

Tire/Wheel Base Calibration

    • Read Tire/Wheel Base/Booster Info.
    • New Tire/Wheel Base/Booster Info

Important: If the EBCM is not calibrated with the correct brake assist system information, Hydromax diagnostic capabilities may be disabled.

This function allows the technician to read the current EBCM tire size, wheel base and brake assist system calibrations or to program the EBCM with the correct tire size, wheel base and brake assist system information for a specific vehicle. This procedure must be performed if different size tires are installed on the vehicle or if a new EBCM is installed in the vehicle.