LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Buick >> 1995 >> Roadmaster Base >> Repair and Diagnosis >> Brakes >> Traction Control >> Anti-Lock Brake System >> Testing >> Automatic Tests
April 5, 2026: LEMON Manuals is launched! Read the announcement.

Automatic Tests

Turn ignition on. Using Tech 1, select F4: MISC TESTS and then F1: AUTO TEST. Press ENTER when ready. Valves can be heard and felt cycling from hydraulic control unit. Have assistant verify pump motor is turned on. See DIAGNOSTIC TROUBLE CODE (DTC) table if DTCs are set. See DIAGNOSTIC TROUBLE CODE CHARTS. After all diagnosis and repairs are completed, clear DTCs and verify operation. AUTO test is performed automatically by EBCM once during each ignition cycle when vehicle reaches approximately 4 MPH.

DIAGNOSTIC TROUBLE CODE (DTC)

DTC (1)Definition
12 Diagnostic System Operational
21 Right Front Wheel Speed Sensor Circuit
23 Right Front Wheel Speed Sensor Continuity
25 Left Front Wheel Speed Sensor Circuit
27 Left Front Wheel Speed Sensor Continuity
28 Wheel Speed Sensor Frequency Error
35 Rear Axle (Wheel) Speed Sensor Circuit
37 Rear Axle (Wheel) Speed Sensor Continuity
41 Right Front Inlet Solenoid Valve Fault
42 Right Front Outlet Solenoid Valve Fault
45 Left Front Inlet Solenoid Valve Fault
46 Left Front Outlet Solenoid Valve Fault
55 Rear Inlet Solenoid Valve Fault
56 Rear Outlet Solenoid Valve Fault
61 Pump Motor Or Relay Fault
63 Solenoid Valve Relay Fault
71 EBCM Fault
85 Low Voltage
(1) Always perform ABS system functional check before using DIAGNOSTIC TROUBLE CODE CHARTS. See Figure.