Initial Inspection and Diagnostic Overview

This section contains information on diagnosing conditions which can affect operation of the Teves Mark IV-G ABS and the Teves Mark IV-G ABS With Traction Control. Specifically, this section should be used to help diagnose mechanical conditions which result in any of the following.
1. Anti-Lock Warning Lamp turned on.
2. Brakes Lock on Hard Application
3. Diagnosis of conditions such as brake noise, brake pulsation, lack of power assist, turning on of the Red Brake Warning Lamp or vehicle vibration during normal braking, should be directed to Brakes Testing and Inspection.
4. In order to effectively diagnose an ABS or ABS with traction control system condition, it is important to read and understand the ABS/ABS with traction control system description. Then follow the required diagnostic procedures outlined in this section.
5. Many conditions that generate customer complaints may be normal operating conditions, but are judged to be a problem due to not being familiar with the ABS or the ABS with traction control operation. These conditions can be recognized without performing extensive diagnostic work, given adequate understanding of the operating principles and performance characteristics of the ABS or the ABS with traction control system. The ABS and the ABS with traction control uses an electronic control module refered to as the Controller Antilock Brakes CAB. This module is designed to withstand normal current draws associated with vehicle operation. However care must be taken to avoid overloading the CAB circuits. In testing for open or short circuits, do not ground or apply voltage to any of the circuits unless instructed to do so by the appropriate diagnostic procedure. These circuits should only be tested using a high impedance multi-meter, special tools or the DRB scan tool as described in this section. Power should never be removed or applied to any control module with the ignition in the ON position. Before removing or connecting battery cables, fuses, or connectors, always turn the ignition to the OFF position.

NOTE: The following are general precautions which should be observed when servicing and diagnosing the Teves Mark IV-G ABS or the Teves Mark IV-G ABS With Traction Control. Failure to observe these precautions may result in ABS system damage.

6. If welding work is to be performed on a vehicle using an arc welder, the CAB should be disconnected before the welding operation begins.
7. The CAB connector should never be connected or disconnected with the ignition in the on position.
8. Some components of the Teves Mark IV-G ABS and the Teves Mark IV-G ABS with traction control are not serviced separately and must be serviced as complete assemblies. Do not disassemble any component which is designated as being non-serviceable.