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Idle Speed Motor Position Sensor: Testing and Inspection


1. Disconnect motor position sensor electrical connector and measure resistance between terminals 1 and 3. Resistance should be 4000 to 6000 ohms.
2. Disconnect idle speed control servo electrical connector.
3. Apply approximately 6 volts (DC) between terminals 1 and 2 of idle speed control servo electrical connector and check resistance between terminals 1 and 2 of motor position sensor electrical connector.
4. Ensure MPS resistance changes smoothly from approximately .5 ohms to value obtained in step 1, as idle speed control servo is activated.
5. If obtained resistance values are not within limits, replace idle speed control servo assembly.