Test 20C - Open/Shorted Input Speed Sensor (DTC 56)

NOTE: Perform TEST 2A or 20A before proceeding with this test. For connector terminal identification, see CONNECTOR IDENTIFICATION . For wiring diagrams, see WIRING DIAGRAMS . Perform VERIFICATION TEST VER-1A after each repair.

CAUTION: Always turn ignition switch to OFF position prior to disconnecting or connecting any module connector.

If output speed sensor RPM is zero, go to TEST 20D . Ensure ignition is off. Disconnect Transmission Control Module (TCM) connector. Inspect terminals No. 13 and 52 of TCM connector. Clean or repair as needed.
Use scan tool in ohmmeter mode. Measure resistance at terminal No. 52 of TCM connector. If resistance is more than 5 ohms for all models, go to step 4). If resistance is less than 5 ohms, go to next step.
Disconnect input speed sensor connector. Repeat step 2). If resistance is less than 5 ohms for all models, repair input speed sensor circuit for short to ground. If resistance is 5 ohms or greater, replace input speed sensor.
Use external ohmmeter. Measure resistance between terminals No. 13 and 52 of TCM connector. If resistance is 300-1200 ohms, replace TCM. If resistance is not 300-1200 ohms, go to next step.
Disconnect input speed sensor connector. Use external ohmmeter. Measure resistance between terminal No. 2 of input speed sensor connector and terminal No. 52 of TCM connector. If resistance is 5 ohms or greater, repair open input speed sensor circuit. If resistance is less than 5 ohms, go to next step.
Use external ohmmeter. Measure resistance between terminal No. 1 of input speed sensor connector and terminal No. 13 of TCM connector. If resistance is 5 ohms or greater, repair open sensor ground circuit. If resistance is less than 5 ohms, replace input speed sensor.