Test TC-87B - Speed Control Switch Always Low
NOTE:
For appropriate wiring diagram, see WIRING DIAGRAMS
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- Turn ignition off. Using scan tool, read speed control switch voltage under sensors. If voltage is less than one volt, go to step 3). If voltage is one volt or more, go to next step.
- 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. Refer to INACTIVE TROUBLE CODE CONDITION under SELF-DIAGNOSTIC SYSTEM. Test is complete. Perform TEST SC-VER .
- Disconnect speed control ON/OFF switch connector. Inspect connector and terminals for damage. Repair connector and terminals as necessary and perform TEST SC-VER . If connector and terminals are okay, go to next step.
- Read speed control switch voltage. If voltage changes to 5 volts, replace speed control ON/OFF switch and perform TEST SC-VER . If voltage does not change to 5 volts, go to next step.
- Disconnect speed control CANCEL switch connector. Inspect connector and terminals for damage. Repair connector and terminals as necessary and perform TEST SC-VER . If connector and terminals are okay, go to next step.
- Read speed control switch voltage. If voltage changes to 5 volts, replace speed control CANCEL switch and perform TEST SC-VER . If voltage does not change to 5 volts, go to next step.
- Turn ignition off. Disconnect Powertrain Control Module (PCM) connectors. Inspect connectors and terminals for damage. Repair connectors and terminals as necessary and perform TEST SC-VER . If connectors and terminals are okay, go to next step.
- Using an external ohmmeter, check resistance between PCM Gray connector terminal C32, speed control switch signal circuit (Pink wire) and PCM Black connector terminal A4, ground circuit (Black/Light Blue wire). If resistance is 5 ohms or more, replace PCM and perform TEST SC-VER . If resistance is less than 5 ohms, repair speed control switch signal circuit shorted to ground circuit and perform TEST SC-VER .