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Brakes - System Bleeding Upon ABS Module Replacement

Group:
CHASSIS

Number:
06-50-002

Date:
FEBRUARY, 2006

Model:
2006 SONATA & AZERA

Subject:
BRAKE BLEED PROCEDURE WHEN REPLACING THE ABS MODULE

DESCRIPTION:

When replacing the ABS module with a genuine Hyundai service part, it is not necessary to perform the High Scan electronic brake bleed procedure.

NOTE:
Genuine Hyundai replacement ABS modules have a filled secondary circuit.

WARNING:
Performing the High Scan electronic brake bleed procedure while air is in the primary brake circuit may trap air in the ABS module, which will be released during the ABS self check or when ABS/TCS/ESC is activated.





The ABS module consists of two fluid circuits, a primary and secondary circuit. During normal operation the primary brake circuit passes through the ABS module without obstruction. The secondary circuit consists of a rotary pump, inlet valves and outlet valves. The secondary circuit is only opened during ABS/TCS/ESC activation or during the ABS self check.

During ABS/TSC/ESC activation, the ABS module actuates the rotary pump, inlet and outlet valves to modulate brake pressure at individual wheels. During the ABS self check, completed when the vehicle exceeds approximately 10 mph after each new key cycle, the ABS module actuates the rotary pump, inlet and outlet valves to check functionality.

After replacing the ABS module, the primary circuit must be free from air to prevent air from entering the secondary circuit.