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Test FC-7A - No Vehicle Speed Sensor Signal (DTC 15)

NOTE: For connector terminal identification, see CONNECTOR IDENTIFICATION . For appropriate wiring diagram, see WIRING DIAGRAMS  at end of article.
  1. Raise vehicle so drive wheels are free to spin. Start engine. Using DRB-II, read Vehicle Speed Sensor (VSS) signal. Put transmission in any forward gear. If DRB-II displays more than zero MPH, go to next step. If DRB-II does not display more than zero MPH, go to step 4).
  2. Condition required to set fault is not present at this time. NO VEHICLE SPEED SENSOR SIGNAL fault sets if Powertrain Control Module (PCM) does not see a VSS signal at PCM terminal No. 47 (White/Orange wire) under road load conditions. Possible causes are: open or shorted VSS signal circuit (White/Orange wire), no signal from Transmission Control Module (TCM), failed Daytime Running Light (DRL) module (if equipped) or failed Powertrain Control Module (PCM). Go to next step.
  3. Inspect all related wiring and connectors and repair as necessary. Perform VERIFICATION PROCEDURE VER-2. If no problems were found with wiring and connectors, see INACTIVE FAULT CONDITION. Perform VERIFICATION PROCEDURE VER-2.
  4. Using DRB-II, read electronic automatic transmission fault codes. If Code(s) 50-58 is displayed, go to TRANSMISSION SERVICE & REPAIR section. If Code(s) 50-58 is not displayed, turn ignition off.
  5. Disconnect Transmission Control Module (TCM) connector. Turn ignition on. Put DRB-II in voltmeter mode. Using DRB-II, check voltage on TCM connector terminal No. 58, Vehicle Speed Sensor (VSS) signal circuit (White/Orange wire). If voltage is more than 4 volts, go to step 9).
  6. If voltage is less than 4 volts, turn ignition off. Disconnect Powertrain Control Module (PCM) connector. If vehicle is equipped with Daytime Running Lights (DRL) or a mechanical dash, go to TEST FC-7B. If vehicle is not equipped with Daytime Running Lights (DRL) or a mechanical dash, go to next step.
  7. Using an external ohmmeter, check resistance of signal circuit (White/Orange wire) between TCM connector terminal No. 58 and PCM connector terminal No. 47. If resistance is more than 5 ohms, repair open in White/Orange wire. Perform VERIFICATION PROCEDURE VER-2.
  8. If resistance is less than 5 ohms, put DRB-II in ohmmeter mode. Using DRB-II, check resistance of PCM connector terminal No. 47, signal circuit (White/Orange wire). If resistance is less than 5 ohms, repair short to ground in White/Orange wire. Perform VERIFICATION PROCEDURE VER-2. If resistance is more than 5 ohms, replace PCM. Perform VERIFICATION PROCEDURE VER-2.
  9. Using DRB-II, read vehicle speed. Connect a jumper wire to TCM connector terminal No. 58 (White/Orange wire). While observing DRB-II display, tap other end of jumper wire to ground. If DRB-II displayed vehicle speed more than zero MPH, replace TCM. Perform VERIFICATION PROCEDURE VER-2.
  10. If DRB-II did not display more than zero MPH, turn ignition off. Disconnect Powertrain Control Module (PCM) connector. Using an external ohmmeter, check resistance of signal circuit (White/Orange wire) between TCM connector terminal No. 58 and PCM connector terminal No. 47.
  11. If resistance is less than 5 ohms, replace PCM. Perform VERIFICATION PROCEDURE VER-2. If resistance is more than 5 ohms, repair open in White/Orange wire. Perform VERIFICATION PROCEDURE VER-2.
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