How To Use System Tests
- DO NOT perform any SYSTEM TEST unless specifically instructed by a QUICK TEST procedure. Follow each test step in order until fault is found. DO NOT replace any part unless directed to do so. When more than one DTC is retrieved, start with first DTC displayed.
- SYSTEM TESTS ensure electrical circuits are okay before sensors or other components are replaced. Always test circuits for continuity between sensor and PCM. Test all circuits for short to power, opens or short to ground. Voltage Reference (VREF) and Voltage Power (VPWR) circuits should be tested with ignition switch turned to ON position or as specified in SYSTEM TESTS.
- 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 (wiring harness side). Isolate both ends of a circuit and turn ignition switch to OFF position when checking for shorts or continuity, unless instructed otherwise.
- Disconnect solenoids and switches from harness before measuring continuity and resistance or applying voltage. After each repair, check all component connections and repeat QUICK TEST under DIAGNOSIS & TESTING.
- An open circuit is defined as a resistance reading of 5 ohms or more. This specification tolerance may be too high for some items in EEC-V system. If resistance approaches 5 ohms, always clean suspect connector and coat with protective dielectric silicone grease. A short is defined as a resistance reading of less than 10 k/ohms, unless stated otherwise in SYSTEM TESTS.