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Engine Speed Sensor: Testing and Inspection

Speed sensor, checking
Work sequence





- Unplug gray connector 2 from plenum panel mounting





- Connect ohmmeter between terminals 1 and 2 of unplugged connector
^ specification: 1 K ohm

If specification NOT OK
- Replace engine rpm sensor

If specification OK
- Connect ohmmeter between terminals 1 and 3 then 2 and 3 of unplugged connector
^ specification: infinite ohm

If specification NOT OK
- Replace engine rpm sensor

If specifications OK
- Check wiring and connectors between sensor and control unit as follows
- Remove control unit cover panel located on passenger side footwell





- Unplug control unit connector





- Using ohmmeter, check between terminals of speed sensor connector C and control unit connector A
^ Connector C terminal (1) and control unit connector A terminal (29)
^ Connector C terminal (2) and control unit connector A terminal (11)
^ Connector C terminal (3) and control unit connector A terminal (28)
^ each specification: approx. 0 ohm

If specifications NOT OK
- check for open circuit in wiring between engine rpm sensor and control unit

If wiring OK replace control unit
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