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Makes 🢒 GMC_Truck 🢒 2004 🢒 Savana - AWD 🢒 Preface 🢒 Cautions and Notices 🢒 Antilock Brake System Automated Bleed Procedure

Antilock Brake System Automated Bleed Procedure With JL4

Notice: When adding fluid to the brake master cylinder reservoir, use only Delco Supreme 11®, GM P/N 12377967 (Canadian P/N 992667), or equivalent DOT-3 brake fluid from a clean, sealed brake fluid container. The use of any type of fluid other than the recommended type of brake fluid, may cause contamination which could result in damage to the internal rubber seals and/or rubber linings of hydraulic brake system components.

Notice: Avoid spilling brake fluid onto painted surfaces, electrical connections, wiring, or cables. Brake fluid will damage painted surfaces and cause corrosion to electrical components. If any brake fluid comes in contact with painted surfaces, immediately flush the area with water. If any brake fluid comes in contact with electrical connections, wiring, or cables, use a clean shop cloth to wipe away the fluid.

Important: The following procedures may be performed on vehicles equipped with option code JL4, Vehicle Stability Enhancement System (VSES).

Pre-charge Bleed

The Pre-charge bleed procedure is to be performed when air may have been introduced into the precharge pump inlet hose, the precharge pump or the combination valve. Perform the procedure as follows.

Important: If the brake system warning lamp is illuminated, DO NOT allow the vehicle to be driven until the concern is diagnosed and repaired. Refer to Symptoms - Hydraulic Brakes .

  1. Ensure that the master cylinder reservoir is filled to at least the minimum-fill level with Delco Supreme 11, GM P/N 12377967 (Canadian P/N 992667), or equivalent DOT 3 brake fluid from a clean, sealed container.
  2. Ensure the master cylinder reservoir cap is ON securely.
  3. Install a scan tool.
  4. Turn ON the ignition.
  5. Select the VSES Special Functions menu on the scan tool.
  6. Select Pre-charge Bleed.
  7. Press the On key. The precharge pump runs for approximately 3 seconds, circulating fluid from the master cylinder fluid reservoir, through the precharge pump and combination valve, then back to the master cylinder.
  8. Evaluate the feel of the brake pedal. If the pedal feels spongy, perform a base brake system bleed. Refer to Hydraulic Brake System Bleeding .
  9. Ensure that the master cylinder reservoir is filled to at least the minimum-fill level with Delco Supreme 11, GM P/N 12377967 (Canadian P/N 992667), or equivalent DOT 3 brake fluid from a clean, sealed container.

Automated Bleed

The Automated Bleed procedure is to be performed when the brake pressure modulator valve (BPMV) is replaced. Perform the procedure as follows.

Important: The base brake system must be bled before proceeding. Refer to Hydraulic Brake System Bleeding .

Important: If the brake system warning lamp is illuminated, DO NOT allow the vehicle to be driven until the concern is diagnosed and repaired. Refer to Symptoms - Hydraulic Brakes .

  1. Ensure that the master cylinder reservoir is filled to at least the minimum-fill level with Delco Supreme 11, GM P/N 12377967 (Canadian P/N 992667), or equivalent DOT 3 brake fluid from a clean, sealed container.
  2. Ensure the master cylinder reservoir cap is ON securely.
  3. Install a scan tool.
  4. Turn ON the ignition.
  5. Select the VSES Special Functions menu on the scan tool.
  6. Select Pre-charge Bleed.
  7. Press the On key. The precharge pump runs for approximately 3 seconds, circulating fluid from the master cylinder fluid reservoir, through the precharge pump and combination valve, then back to the master cylinder.
  8. Select Automated Bleed.
  9. Press the On key. The precharge pump and ABS pump run for approximately 6 seconds while air is purged from the BPMV.
  10. Ensure that the master cylinder reservoir is filled to at least the minimum-fill level with Delco Supreme 11, GM P/N 12377967 (Canadian P/N 992667), or equivalent DOT 3 brake fluid from a clean, sealed container.
  11. Perform a base brake system bleed. Refer to Hydraulic Brake System Bleeding .
  12. Evaluate the feel of the brake pedal. If the pedal feels spongy, repeat steps 1-11. If the pedal feel is acceptable, proceed to the next step.
  13. Ensure that the master cylinder reservoir is filled to at least the minimum-fill level with Delco Supreme 11, GM P/N 12377967 (Canadian P/N 992667), or equivalent DOT 3 brake fluid from a clean, sealed container.

Antilock Brake System Automated Bleed Procedure Without JL4

Notice: When adding fluid to the brake master cylinder reservoir, use only Delco Supreme 11®, GM P/N 12377967 (Canadian P/N 992667), or equivalent DOT-3 brake fluid from a clean, sealed brake fluid container. The use of any type of fluid other than the recommended type of brake fluid, may cause contamination which could result in damage to the internal rubber seals and/or rubber linings of hydraulic brake system components.

Notice: Avoid spilling brake fluid onto painted surfaces, electrical connections, wiring, or cables. Brake fluid will damage painted surfaces and cause corrosion to electrical components. If any brake fluid comes in contact with painted surfaces, immediately flush the area with water. If any brake fluid comes in contact with electrical connections, wiring, or cables, use a clean shop cloth to wipe away the fluid.

Important: The base hydraulic brake system must be bled before performing this automated bleeding procedure. If you have not yet performed the base hydraulic brake system bleeding procedure, refer to Hydraulic Brake System Bleeding before proceeding.

  1. Install a scan tool to the vehicle.
  2. Start the engine and allow the engine to idle.
  3. Depress the brake pedal firmly and maintain steady pressure on the pedal.
  4. Using the scan tool, begin the automated bleed procedure.
  5. Follow the instructions on the scan tool to complete the automated bleed procedure. Release the brake pedal between each test sequence.
  6. Turn the ignition OFF.
  7. Remove the scan tool from the vehicle.
  8. Fill the brake master cylinder reservoir to the maximum-fill level with Delco Supreme 11®, GM P/N 12377967 (Canadian P/N 992667), or equivalent DOT-3 brake fluid from a clean, sealed brake fluid container.
  9. Bleed the hydraulic brake system. Refer to Hydraulic Brake System Bleeding .
  10. With the ignition OFF, apply the brakes 3-5 times, or until the brake pedal becomes firm, in order to deplete the brake booster power reserve.
  11. Slowly depress and release the brake pedal. Observe the feel of the brake pedal.
  12. If the brake pedal feels spongy, repeat the automated bleeding procedure. If the brake pedal still feels spongy after repeating the automated bleeding procedure, inspect the brake system for external leaks. Refer to Brake System External Leak Inspection .
  13. Turn the ignition key ON, with the engine OFF. Check to see if the brake system warning lamp remains illuminated.
  14. If the brake system warning lamp remains illuminated, DO NOT allow the vehicle to be driven until it is diagnosed and repaired. Refer to Symptoms - Hydraulic Brakes .
  15. Drive the vehicle to exceed 13 km/h (8 mph) to allow ABS initialization to occur. Observe brake pedal feel.
  16. If the brake pedal feels spongy, repeat the automated bleeding procedure until a firm brake pedal is obtained.