DTC 38

DTC 38 Left Front ESB Will Not Hold Motor:

Circuit Description:
This DTC is designed to detect a slipping left front ESB. During initialization and braking, the left front motor is rehomed. If the ESB slips, the motor/piston will move. During the next key "ON" initialization, a rehome of the motor verifies the motor/piston remained at the home position. If motor movement is detected, the ESB must be slipping.

DTC Will Set When:
DTC 38 can be set during initialization. If the EBCM detects that the ESB could not hold the piston in the home position, a malfunction exists. DTC 86 is always set with DTC 38.

Action Taken:
If an ESB cannot hold a piston in the home position, the piston may be backdriven when the brake pedal is applied, causing the brake pedal to drop. A malfunction DTC is stored, ABS is disabled, and the ABS warning lamp and the red "BRAKE" warning lamp are turned "ON."

DTC Chart Test Description:
Number(s) below refer to circled number(s) on the diagnostic chart.
1. Checks the left front ESB. A broken or defective ESB would result in the left front piston being backdriven by hydraulic pressure and pedal movement would result.
2. Ensures that the proper motor circuits are located in the proper connector cavities.
3. Checks for high resistance in the motor "HIGH" circuitry.
4. Checks for high resistance in the motor "LOW" circuitry.
5. Checks for proper resistance of the motor windings.
6. Checks for poor terminal contact or corrosion in the connectors.
7. Checks for a malfunctioning EBCM.

Diagnostic Aids:
An "Intermittent" malfunction in this DTC may result from a mechanical part of the system that sticks, binds, or slips.

The frequency of the malfunction can be checked by using the enhanced diagnostic function of the Tech 1.

The static modulator test function of the Tech 1 or T-1OO may be used to locate an intermittent malfunction associated with the ESB.