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Home >> Plymouth >> 1988 >> Horizon Automatic >> Repair and Diagnosis >> Engine Performance >> System >> 2.2L/2.5L TBI Tests W/Codes >> Diagnostic Trouble Code (DTC) Identification >> Dr3, Code 15 - Speed Sensor Circuit
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Dr3, Code 15 - Speed Sensor Circuit

  1. Connect DRB II. Start engine. Disconnect speed sensor connector. Put system into Engine Running Test "71". Connect jumper wire between the Black and White/Orange terminals of speed sensor. Make and break this connection. If display on DRB II changes, replace speed sensor. If display does not change, go to next step.
  2. Turn engine off and disconnect speed sensor. Disconnect 60-pin connector from SMEC. Connect an ohmmeter between White/Orange wire at cavity No. 48 of 60-pin connector and White/Orange wire at speed sensor harness connector. If ohmmeter reads continuity, go to next step. If ohmmeter is not reading continuity, repair White/Orange wire in cavity No. 48 of 60-pin connector for an open circuit to speed sensor connector.
    Fig 1: Jumpering Speed Sensor
    G55969
    Fig 2: Connection Between Speed Sensor & 60-Pin Connection.
    G55970
  3. With engine off, disconnect speed sensor and 60-pin SMEC connector. Connect an ohmmeter between Black/Light Blue wire at cavity No. 4 of 60-pin connector and Black wire terminal of speed sensor harness connector. If ohmmeter reads continuity, replace SMEC. Before replacing SMEC, ensure cavity No. 48 is not damaged causing a poor connection. If ohmmeter is not reading continuity, repair Black/Light Blue or Black wire of speed sensor harness connector for an open circuit to wiring harness splice.