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Test TC-87B - Speed Control Switch Always Low

NOTE: For connector terminal ID, see CONNECTOR IDENTIFICATION DIRECTORY. For component location see wiring diagram in the WIRING DIAGRAMS article.
  1. Using scan tool, read Speed Control (S/C) switch sensor voltage. If voltage is less than one volt, go to step 3). If voltage is one volt or more, go to next step.
  2. Condition required to set DTC is not present at this time. SPEED CONTROL SWITCHES DTC sets if Powertrain Control Module (PCM) senses actual switch state does not match intended switch state. Possible causes are: shorted switch circuit, defective PCM, open switch ground circuit or shorted or open switch. See INACTIVE DTC CONDITION. Test is complete. Perform TEST VER-4A.
  3. Turn ignition off. Disconnect S/C ON/OFF switch connector. Inspect connector and terminals for damage. Repair connector and terminals as necessary and perform TEST VER-4A. If connector and terminals are okay, go to next step.
  4. Read S/C switch sensor voltage. If voltage changes to 5 volts, replace S/C ON/OFF switch and perform TEST VER-4A. If voltage does not change to 5 volts, go to next step.
  5. Disconnect S/C CANCEL switch connector. Inspect connector and terminals for damage. Repair connector and terminals as necessary and perform TEST VER-4A. If connector and terminals are okay, go to next step.
  6. Read S/C switch sensor voltage. If voltage changes to 5 volts, replace S/C CANCEL switch and perform TEST VER-4A. If voltage does not change to 5 volts, go to next step.
  7. Turn ignition off. Using an external ohmmeter, check resistance between PCM Gray connector, S/C switch signal circuit and ground circuit (Black/Light Blue wire). If resistance is less than 5 ohms, repair S/C switch signal circuit shorted to ground circuit and perform TEST VER-4A. If resistance is 5 ohms or more, go to next step.
  8. Disconnect Powertrain Control Module (PCM) connectors. Inspect connectors and terminals for damage. Repair connectors and terminals as necessary and perform TEST VER-4A. If connectors and terminals are okay, go to next step.
  9. Turn ignition off. Using an external ohmmeter, check resistance between ground and PCM Gray connector, S/C switch signal circuit. If resistance is less than 5 ohms, repair S/C switch signal circuit shorted to ground and perform TEST VER-4A. If resistance is 5 ohms or more, replace PCM and perform TEST VER-4A.
NOTE: A break in test sequence occurs at this point. Sequence skips from TEST TC-87B to TEST TC-101A. No tests have been omitted.
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