Initial Inspection and Diagnostic Overview

A visual inspection consists of physically looking for the possible cause of a malfunction. A careful and thorough visual inspection of components may quickly identify the cause of a malfunction and eliminate the need for diagnostic testing.

Perform the following visual inspections before doing any diagnostic testing.

If a malfunction is not resolved by the visual inspection, proceed with diagnostic testing.

BRAKE FLUID LEVEL Visually inspect for the proper fluid level within the fluid reservoir.

HYDRAULIC CONTROL UNIT (FRONT AND REAR) Visually inspect the hydraulic assemblies for leaks and for damaged or disconnected connectors.

RELAYS & FUSES Visually inspect that all ABS relays and fuses are properly installed.

WHEEL SPEED SENSOR CONNECTORS Visually inspect both front wheel speed sensor connectors for damage or disconnection. Inspect the rear axle speed sensor connectors.

BRAKE FLUID LINES Visually inspect brake fluid lines for any leaks or damage.

WHEEL SPEED SENSORS Visually inspect all three wheel speed sensors and tone wheels for any damage.

CONTROLLER - ANTI LOCK BRAKE (CAB) Visually inspect the CAB for a secure mounting and the CAB connector for damage or loose connection.

BASE BRAKE SYSTEM Visually inspect the condition of the parking brake, rotors, drums, and calipers.