Diagnostic Aids
Following information should be noted during testing:
- Ensure 5-amp ENGINE is okay.
- All voltage readings given in test procedures are based on values obtained using a standard DVOM.
- When instructed to inspect a wiring harness, perform both a visual inspection and a continuity test.
- When making voltage checks, ground connections should be made at negative battery terminal or cast iron surface of engine.
- When making measurements on a wiring harness or connector, perform a wiggle test while measuring.
- When checking voltage, ground reading is defined as value of less than one volt. Battery voltage is defined as value of 10-14 volts.
- DO NOT measure voltage or resistance at PCM. DO NOT connect any test light unless specified in testing procedure. All measurements are made by probing rear of connector.
- Isolate both ends of a circuit and turn ignition off when checking continuity.
- An open circuit is defined as a resistance reading of greater than 5 ohms. This specification tolerance may be too much for some items in EEC system. If resistance approaches 5 ohms, always clean suspect connector and coat it with protective di-electric silicone grease. A short is defined as a resistance reading of less than 10,000 ohms to ground, unless stated otherwise.
- Test procedures are intended to identify faulty components or wiring while fault is present. If complaint is an intermittent condition, refer to TESTS W/O CODES article in the ENGINE PERFORMANCE section.