ABS System Description

DESCRIPTION
The Teves Mark IV-G ABS and ABS with traction control systems are equipped with a self diagnostic capability which may be used to assist in isolation of trouble codes. The features of the self diagnostics are described below.

INTERMITTENT DIAGNOSTIC TROUBLE CODES
As with virtually any electronic system, intermittent faults in the ABS system may be difficult to accurately diagnose. Most intermittent faults are caused by faulty electrical connections or wiring. When an intermittent fault is encountered, check suspect circuits for:
1. Poor mating of connector halves or terminals not fully seated in the connector body.
2. Improperly formed or damaged terminals. All connector terminals in a suspect circuit should be carefully reformed to increase contact tension.
3. Poor terminal to wire connection. This requires removing the terminal from the connector body to inspect.
4. Pin presence in the connector assembly
5. Proper ground connections. Check all ground connections for signs of corrosion, tight fasteners, or other potential defects. Refer to wiring diagram manual for ground locations.
6. If a visual check does not find the cause of the problem, operate the car in an attempt to duplicate the condition and record the Fault code.
7. Most failures of the ABS system will disable ABS function for the entire ignition cycle even if the fault clears before key-off. There are some failure conditions, however, which will allow ABS operation to resume during the ignition cycle in which a failure occurred if the failure conditions are no longer present. The following conditions may result in intermittent illumination of the ABS Warning Lamp. All other failures will cause the lamp to remain on until the ignition switch is turned off. Circuits involving these inputs to the Controller Antilock Brake (CAB) should be investigated if a complaint of intermittent warning system operation is encountered.
8. Low system voltage. If Low System Voltage is detected by the CAB, the CAB will turn on the ABS Warning Lamp until normal system voltage is achieved. Once normal voltage is seen at the CAB, normal operation resumes.
9. Additionally, any condition which results in interruption of electrical current to the CAB or modulator assembly may cause the ABS Warning Lamp to turn on intermittently.