Intermittent Problem Diagnosis

Intermittent fault testing requires duplicating circuit or component failure to identify the problem. These procedures may lead to the computer setting a fault code (on some systems) which may help in diagnosis.

If problem vehicle does not produce fault codes, monitor voltage or resistance values using a Land Rover TestBook, an OBD-II scan tool or a DVOM while attempting to reproduce conditions causing intermittent fault. A status change indicates a fault has been located.

Use a Land Rover TestBook, an OBD-II scan tool or a DVOM to pinpoint faults. When monitoring voltage, ensure ignition switch is in ON position or engine is running. Ensure ignition switch is in OFF position or negative battery cable is disconnected when monitoring circuit resistance. Status changes during test procedures indicate area of fault.