General Pinpoint Test Notes

NOTE: There can be several breaks in the step numbering sequence of a Pinpoint Test. The breaks are due to previous chart references to these testing procedures. No test procedures have been omitted.

NOTE: If a Pinpoint Test directs you to use the CONTINUOUS MONITOR MODE (WIGGLE TEST) , the OUTPUT STATE CHECK , or the CYLINDER BALANCE TEST - SEFI ENGINES procedures, they can be found in this article under the EEC-IV FUNCTIONAL TESTS head.

DO NOT perform any Pinpoint Test unless directed to do so by the QUICK TEST procedure. Follow each test step in order until fault is found. DO NOT replace any part unless directed to do so.

When directed to a Pinpoint Test by the Quick Test, always read the Introduction of the Pinpoint Test for special notes or schematics. After service, rerun the Quick Test to ensure that service was effective.

Pinpoint Tests require that you prove electrical circuits are okay before replacement of EEC-IV components. An open circuit is defined as any resistance reading greater than 5 ohms. This specification tolerance may be too high for some items in the EEC-IV system. If resistance approaches 5 ohms, always clean the suspected connector and coat with protective dielectric silicone grease.

A short is defined as any resistance reading less than 10 k/ohms to ground, unless otherwise specified. A breakout box, which connects to the vehicle harness at the ECA, is necessary to perform most Pinpoint Tests. References to Test Pin No. found in Pinpoint Test steps refer to test terminals on the manufacturer's breakout box. Circuit diagrams at the beginning of each test will identify circuit and wire colors.

Pinpoint TESTS are grouped in the following categories.

A-C: No Start & Voltage Tests
DA-DQ: Input Sensor Tests
FA-FF: Additional Input Component Tests
H-J: Fuel Control Systems
KC-X: ECA (Processor) Output Tests