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Home >> BMW >> 1989 >> 635CSi Automatic >> Repair and Diagnosis >> Engine Performance >> System >> System/Component Tests >> Engine Sensors & Switches >> Engine Speed/Reference Point Sensor
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Engine Speed/Reference Point Sensor

  1. Sensor can be checked with ohmmeter or oscilloscope. Ensure ignition is off. Unplug sensor. Sensor is located on front of engine near crankshaft pulley.
  2. Resistance across 2 connector terminals (sensor side) should be as specified. See ENGINE SPEED/REFERENCE POINT SENSOR table. Connect ohmmeter between each sensor terminal and engine block. Ohmmeter should not show continuity. If so, replace sensor.
  3. To check sensor with oscilloscope, unplug sensor. Connect oscilloscope leads across the 2 sensor terminals. Remove fuel pump relay to prevent engine from starting. Crank engine. Oscilloscope should show a sign wave as engine is cranked.
ENGINE SPEED/REFERENCE POINT SENSOR

Application Ohms
All Models 490-550