How To Use Pinpoint Tests

NOTE: Inspect all wiring, harnesses, connectors, and components for damage, overheating, shorting, or looseness. If any defect is found, repair as necessary before proceeding to any PINPOINT TEST.

1) Do not perform any PINPOINT TEST unless directed by a QUICK TESTS procedure. Repair all non-EEC related defects. Follow each test step in order until defect is found. DO NOT replace any part unless so directed. When more than one service code exists, start with first code displayed.

2) PINPOINT TESTS require that electrical circuits are okay before replacing sensors or any other components. Always test circuits for continuity between sensor and PCM. Test all circuits for shorts to voltage, opens, or shorts to ground. VREF and VPWR circuits should be tested with KOEO or as specified in PINPOINT TESTS.

3) DO NOT measure voltage or resistance at PCM, or connect any test light unless specified in test procedure. DO NOT pierce wiring. Isolate both ends of a circuit and turn ignition off before testing for shorts or continuity, unless otherwise specified.

4) Disconnect solenoids and switches before testing for circuit continuity or energizing solenoids.

5) An open is defined as any resistance greater than 10,000 ohms unless otherwise specified.

6) To help diagnose circuits to PCM, turn ignition off and disconnect PCM harness. Connect BOB between PCM and PCM harness to perform circuit and pinpoint tests.