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Oil Pressure Gauge Inaccurate (Astro, Safari & "S" Series)

  1. Check for shorts or opens in wiring between oil pressure sending unit and cluster, or for an inoperative oil pressure sending unit. To do so, disconnect oil pressure sending unit at engine. Connect one lead of Instrument Panel Tester (J-33431) to Tan wire and other lead to ground.
  2. Turn ignition switch to "RUN" position and set tester resistance dials to zero (0) ohms. Oil pressure should read low. Now set resistance dials to 35 ohms. Oil pressure gauge should have 7-8 segments lit. Finally, set resistance dials to 90 ohms. Oil pressure gauge should read high.
  3. If fuel gauge responds correctly, replace oil pressure gauge sending unit. If gauge does not respond as indicated, check Tan wire between fuel gauge sending unit and cluster. If wire is okay, replace inoperative cluster.
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