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Home >> Jeep >> 1996 >> Grand Cherokee Limited, 5.2 Y >> Repair and Diagnosis >> External Pages >> Different car >> Section 5 (Engine Controls - Tests W/Codes - 3.3L) >> Diagnostic Charts >> Test TC-27A - No Vehicle Speed Sensor Signal (DTC 15)

Test TC-27A - No Vehicle Speed Sensor Signal (DTC 15)

WARNING: This page is about a different car, the 1994 Eagle Vision, 1994 Dodge Intrepid, and 1994 Chrysler Concorde. However, it is still accessible from the selected car via links, so may be relevant.
NOTE: For circuit & connector terminal identification, see CONNECTOR IDENTIFICATION DIRECTORY . For wiring diagrams, see WIRING DIAGRAMS  section. After each repair, perform TEST VER-2 .
WARNING: Keep hands and feet clear of rotating wheels.
  1. Raise and support vehicle under lower control arms, allowing wheels to spin free. Start engine. Using DRB, read Vehicle Speed Sensor (VSS) MPH. Place transmission in any forward gear. If DRB does not display more than 0 MPH, go to step 4). If DRB displays more than 0 MPH, go to next step.
  2. At this time, the condition required to set trouble code is not present. VEHICLE SPEED SENSOR (VSS) SIGNAL trouble code sets when Powertrain Control Module (PCM) does not see a speed signal under road load conditions. Possible causes are: open or shorted VSS wire, no VSS from Transmission Control Module (TCM), faulty TCM output speed circuit, failed PCM, or failed TCM.
  3. Inspect wiring and connectors. Repair wiring and connectors as required. If wiring and connectors are okay, see INACTIVE TROUBLE CODE CONDITION . Test is complete.
  4. If DRB does not display 0 MPH in step 1), use DRB to read electronic automatic transmission trouble codes.
  5. Turn ignition off. Disconnect Transmission Control Module (TCM) connector. TCM is located in engine compartment between left front fender and battery. Turn ignition on. Using DRB in voltmeter mode, check voltage on TCM connector terminal No. 58 (White/Orange wire). If voltage is more than 4 volts, go to step 9). If voltage is less than 4 volts, go to next step.
  6. Turn ignition off. Disconnect Powertrain Control Module (PCM) connector. PCM is located under air cleaner. If vehicle is equipped with Speed Proportional Steering (SPS), go to TEST TC-27B . If vehicle is not equipped with SPS, go to next step.
  7. Using an external ohmmeter, check resistance of White/Orange wire between PCM connector terminal No. 47 and TCM connector terminal No. 58. If resistance is more than 5 ohms, repair open White/Orange wire. If resistance is less than 5 ohms, go to next step.
  8. Using DRB in ohmmeter mode, check resistance of PCM connector terminal No. 47 (White/Orange wire). If resistance is less than 5 ohms, repair short to ground in White/Orange wire. If resistance is more than 5 ohms, replace PCM.
  9. If voltage is more than 4 volts in step 6), read Vehicle Speed Sensor (VSS) MPH using DRB. Connect one end of a jumper wire to TCM connector terminal No. 58 (White/Orange wire). While observing DRB display, connect other end of jumper wire to chassis ground. If DRB displays vehicle speed more than 0 MPH, replace TCM. If DRB displays vehicle speed less than 0 MPH, go to next step.
  10. Turn ignition off. Disconnect PCM connector. Using an external ohmmeter, check resistance of White/Orange wire between PCM connector terminal No. 47 and TCM connector terminal No. 58. If resistance is less than 5 ohms, replace PCM. If resistance is more than 5 ohms, repair open White/Orange wire.
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