Test Point 4 - Reference Mark Sensor

NOTE: This test requires the use of an oscilloscope. Refer to oscilloscope manufacturer's instructions for hookup and operation.

1. Disconnect reference plug (lower plug in three plug plate in left front of the engine compartment).
2. Connect oscilloscope to center and lower terminals of reference sensor connector.

Reference Signal Oscilloscope Pattern:

3. Crank engine and observe oscilloscope.

Pattern correct, proceed to step 6.
Pattern incorrect, proceed to next step.

4. Measure resistance across same terminals check in previous test.

600 - 1600 ohms, proceed to next step.
Not 600 - 1600 ohms, replace reference. End of test.

5. Check sensor and harness wiring and sensor adjustment. If both check OK, replace reference. End of test.
6. Measure resistance across same terminals check in previous test.

600 - 1600 ohms, proceed to next step.
Not 600 - 1600 ohms, replace reference. End of test.

7. Sensor functioning properly. End of test.