How To Use Circuit Tests

NOTE: In order to allow for a more detailed and complete title to be displayed in the menu screen, specific Circuit Tests are titled "TEST". For example, CIRCUIT TEST MIL is referred to as TEST MIL.

1) DO NOT perform any circuit test unless specifically instructed by a procedure under QUICK TEST or SWITCH MONITOR TEST. Ensure all non-EEC related faults are corrected. Follow each test step in order until fault is found. When more than one code is received, start with first code displayed.

2) Use circuit tests to check electrical circuits before replacing sensors or any other components. Always test circuits for continuity between sensor and PCM. Test all circuits for short to power, opens or short to ground.

NOTE: A short is defined as a resistance value of less than 5 ohms.

3) DO NOT connect any test light or measure voltage or resistance at PCM unless specified in testing procedure. DO NOT pierce wiring. If backprobing is specified, always backprobe harness side of connector. DO NOT probe connector side.

4) Isolate both ends of circuit and turn ignition off whenever checking for shorts or continuity, unless specified otherwise. Disconnect solenoids and switches before checking circuit continuity or energizing solenoids.