DeVille V8-4.6L VIN Y (1998)
Brake Bleeding: Service and Repair
ABS Bleed Procedure
BLEEDING PROCEDURE
The following procedure provides a complete Delco Bosch 5 brake system bleed. The procedure cycles the system valves and runs the pump in order
to purge air from the secondary circuits. The secondary circuits are normally closed off during non-ABS/TCS mode operation and bleeding. Use this
procedure when it is suspected that air has been ingested into the secondary circuits, or after Brake Pressure Modulator Valve (BPMV) replacement.
The following materials are required:
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A Scan Tool
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A pressure brake bleeder capable of producing at least 30 psi with suitable adapters and filled with Delco Supreme II brake fluid obtained from a
sealed container
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A suitable hoist
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An unbreakable plastic bleeder bottle to receive the vented brake fluid, with a clear plastic hose sized to fit snugly on the bleeder valves. The hose
should protrude into the bottle, with the end submerged in brake fluid.
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An assistant to pump the brake pedal
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The suitable safety attire, including safety glasses
BLEED INSTRUCTIONS
1. Raise the vehicle. Support the vehicle.
2. Remove all four tire and wheel assemblies.
3. Inspect the brake system for leaks.
4. Inspect the brake system for component damage.
5. Inspect the battery state of charge.
6. Connect the Scan Tool to the Data Link Connector (DLC).
7. Turn the ignition to RUN. Do not start the engine.
8. Establish communications with the Scan Tool.
9. Select the ABS/TCS system features.
10. Select Special Functions.
11. Select Auto Bleed Procedure.
12. Bleed the base brake system.
13. Follow the Scan Tool driven instructions until the proper brake pedal height is achieved.
14. If any malfunctions are detected, the bleed procedure will be aborted:
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If DTCs are present, the Scan Tool will display DTCs PRESENT or will list the DTCs, depending on when the DTCs were set.
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DTCs can be cleared in the Trouble Codes mode. Refer to the appropriate Diagnostic Trouble Code (DTC) in order to clear the DTC.
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If the test is aborted but no DTCs are listed, refer to "Diagnostic System Check".
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Correct all system malfunctions before attempting the bleed procedure again.
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If a road test is required for diagnosis, and the brake pedal is spongy, perform a conventional brake bleed. Achieve a firm pedal before driving
the vehicle.
15. When the auto bleed procedure is complete, perform the following steps:
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Depress the brake pedal. The brake pedal should be high and firm.
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If the pedal is not firm, inspect the brake system for conditions that might cause the condition. Refer to "Brake System Diagnosis".
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If the brake system is OK, and excess pedal travel persists, repeat the bleed procedure.
16. Disconnect the scan tool.
17. Install the tire and wheel assemblies.
18. Inspect the brake fluid level and fill as necessary.
19. Road test the vehicle while making several ABS/TCS actuations in a suitable area. The brake pedal should remain high and firm throughout the
test.