TROUBLE CODE DETERMINATION (HARD OR INTERMITTENT)
During any diagnostic procedure, you must decide between "hard" codes and "intermittent" codes. Diagnostic charts will not help analyze intermittent failures. Proper use of the Diagnostic Circuit Check chart will determine whether a stored code is "hard" or "intermittent".
An "intermittent" code is one which does not reset itself and is not present while diagnosing vehicle. Intermittent codes are frequently caused by loose connections. A "hard" code will repeat itself during the circuit check and will reset itself while diagnosing vehicle.