System Diagnosis

The throttle body fuel injection system is part of the computerized engine controls system. This system is equipped with "On-Board Diagnostics," which has capability to check several circuits.

If abnormal signals occur often enough to indicate a valid problem, the SMEC will store a fault code. When the fault code is set, the "CHECK ENGINE LIGHT" will come on. This light informs the operator that a malfunction in the system has occurred and service is required.

The SMEC will attempt to compensate for failure of a component by using input from remaining sensors. If the "CHECK ENGINE LIGHT" comes on because of driveability problems, the source of these difficulties may be determined by displaying and recording fault codes. Check FAULT CODES to determine questionable circuit.