Insert Graphic SMITL60439AA

The Expansion spring brakes (ESB) are used on both front and rear actuator motor assemblies. The ESB is a mechanical clutch that prevents the modulator piston from being back driven by hydraulic pressure. If the ESB allows the motor to be back-driven, the antilock telltale lamp will be turned On.

Code 38 sets if:

Left front ESB does not hold motor.

This code can set during initialization 13 km/h (8 mph).

This code can be set after an ABS stop if this channel did not get into ABS.

The ESB is an internal component of the ABS motor pack and can not be serviced separately. If it is determined to be faulty, the motor pack must be replaced.

Use Scan tool to perform ABS motor tension release special test before removing motor pack.

When the ignition is cycled On, the ABS module verifies motors are in home position.

The ABS system will initialize (run motors down then up) when the vehicle is driven at least 13 km/h (8 mph) after start-up.

When attempting to diagnose an intermittent problem, use the Scan tool to review supplemental diagnostic information. The supplemental data can be used to duplicate a problem.

Select Malf History from Scan tool ABS menu.