Note On INTERMITTENTS

The diagnostic procedures in this section may or may not be helpful in determining cause of intermittent problems in anti-lock brake system electrical components. Fault must be present to locate problem effectively using charts.

On all models, most intermittent problems are caused by faulty electrical connections or wiring. When an intermittent failure is encountered, check suspect circuits for:

• Poor mating or connector halves or terminals not fully seated in connector body (backed out).
• Improperly formed or damaged terminals. All connector terminals in a problem circuit should be carefully reformed to increase contact tension.
• Poor terminal-to-wire connection. Requires removing terminal and wire from connector body to inspect.

If visual check does not find cause of problem, the ABS self diagnostic system can be useful in locating suspect circuit in the following manner:

• Display and then clear ABS trouble codes in Electronic Brake Computer Module (EBCM).
• Test drive vehicle attempting to duplicate conditions that caused problem or complaint. Stop vehicle and record any codes set.

Circuits which could possibly cause intermittent operation of "ANTI-LOCK" light include:

• Wheel speed sensor circuits - low or intermittent output.
• Ignition enable circuit - interruption of 12 volt input.
• EBCM switch loop circuit (low fluid/low pressure sensors) - intermittent open.
• Main relay - interruption in coil or switched battery power.