LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Ford >> 1990 >> Probe GL, Standard >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Tests W/Codes - 2.2L >> Self-Diagnostic System >> Diagnostic Formats
April 5, 2026: LEMON Manuals is launched! Read the announcement.

Diagnostic Formats

The EEC system uses 3 diagnostic formats: DIAGNOSTIC ROUTINES, QUICK TESTS and CIRCUIT TESTS (TESTS A1 to D3). The DIAGNOSTIC ROUTINES format categorizes the problem by symptom and directs the technician to the most logical procedure. QUICK TEST procedures allow the technician to identify problem(s), and to retrieve and record service codes.

NOTE: Always start with the QUICK TEST procedures before attempting any CIRCUIT TESTS. The QUICK TEST procedures allow the technician to retrieve and identify any service codes which are used as a reference to find the correct CIRCUIT TEST.

The CIRCUIT TESTS give procedures for testing circuits, sensors and actuators. If a vehicle passes all QUICK TEST procedures, and there are no driveability symptoms or intermittent faults, the EEC system is okay.