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How To Use System Tests

NOTE: For PCM connector terminal identification, see Figure.
  1. DO NOT perform any system test unless instructed by QUICK TEST or another SYSTEM TEST. Follow each test step in order until fault is found. DO NOT replace any part unless directed to do so. When more than one code is retrieved, start with first code displayed.
  2. Circuit 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 on or as specified in tests.
  3. DO NOT make voltage or resistance measurement by probing PCM connector, as harness and connector are easily damaged. DO NOT connect any test light unless specified in testing procedure. All measurements are made by probing rear of connector (wiring harness side) unless instructed otherwise. Isolate both ends of a circuit and turn ignition off when checking for shorts or continuity, unless instructed otherwise.
  4. 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 .
  5. An open is defined as a resistance reading of 5 ohms or more. However, this specification may be too high for some items. If resistance approaches 5 ohms, always clean suspect connector and coat it with protective dielectric silicone grease. A short is defined as a resistance reading of 10 k/ohms or less to ground, unless stated otherwise in test.
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