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Rpm Sensor Test - 5000CS Turbo

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  1. Unplug Gray connector from plenum panel mount bracket (next to ignition coil, center connector). Connect ohmmeter between terminals No. 1 and 2 of unplugged connector. See Figure. Resistance should be 1000 ohms.
  2. If not, replace RPM sensor. If reading is correct, connect ohmmeter between terminals No. 1 and 3, then between terminals No. 2 and 3. Ohmmeter should indicate infinity. If not, replace RPM sensor. If reading is correct, check wiring and connections between reference sensor and control unit as follows.
  3. Remove control unit panel located on passenger side footwell. Unplug ignition control unit connector. See Figure. Using an ohmmeter, check continuity between terminal No. 29 of control unit connector and terminal No. 1 of RPM sensor connector.
  4. Check continuity between terminal No. 11 of control unit connector and terminal No. 2 of RPM sensor connector. Also check continuity between terminal No. 28 of control unit connector and terminal No. 3 of RPM sensor connector.
  5. Ohmmeter reading should be close to zero ohms for all tests. If not, check for open circuit between ignition control unit and RPM sensor. If wiring is okay, replace ignition control unit.