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Test Y: Speed Control Command Switch: Testing

CAUTION: The Powertrain Control Module (PCM) harness connectors must be properly seated and the connector latch properly attached to eliminate possible driveability concerns or a no-start condition. Installing PCM connectors on an angle may cause a bad connection, misdiagnosis and damaged components. Install the connector on where the lever pivots and seats itself. Apply light pressure to get the connector into position on the PCM lever to fully seat the connector.
NOTE: When the PCM engine harness connector is disconnected additional DTCs will be set. All DTCs must be cleared before returning the vehicle to service.
NOTE: When performing KOER switch test, wait five seconds after pressing the trigger to start the test before running through the driver operated controls. The test may also take up to five minutes to complete.

  1. 1) DTC P0565, P0566, P0567, P0568 Or P0569

    DTCs P0565, P0566, P0567, P0568 and P0569 are set if the PCM does not detect when a switch has been pressed during the KOER switch test. Possible causes are:
    • Switch not depressed during test.
    • Worn or damaged speed control switch.
    • Open, grounded, or short to power in SCCS circuit.
    • Open or short in SC GND circuit.
    • Open in power supply circuit.

    Access SCCS PID. Key on, engine off. No switches depressed. Is the voltage reading 6.58-6.78 volts? If yes, go to next step. If voltage reading is 10 volts, go to step  5). If voltage reading is 0 volt, go to step  8).

  2. 2) Check Switch ON Function

    Press ON switch. Does scan tool read 10 volts? If yes, go to next step. If no, go to step  11).

  3. 3) Check Switch OFF Function

    Press OFF switch. Does scan tool read 0 volt? If yes, go to next step. If no, go to step  17).

  4. 4) Command Switches Function

    Press RESUME, COAST, SET/ACCEL switches. Observe voltage reading as each switch is depressed. See SCCS M PID SPECIFICATIONS  table. Do voltage readings agree with voltage values in table plus or minus 0.2 volt? If yes, rerun KOER switch test. If code is still present, install a new PCM. Restore the vehicle. Clear DTCs and retest the system. If no, install a new speed control switch assembly. Restore the vehicle. Clear DTCs and retest the system.
    SCCS M PID SPECIFICATIONS

    Switch Volts
    COAST .68
    SET/ACCEL 2.74
    RESUME 4.66

  5. 5) Check Shorted Command Switch

    Remove horn pad. Disconnect speed control switch harness connector. Is the voltage reading 6.58-6.78 volts? If yes, install a new speed control switch assembly. Restore the vehicle. Clear DTCs and retest the system. If no, go to next step.

  6. 6) Check Clockspring

    Disconnect clockspring connector. Is the voltage reading 6.58-6.78 volts? If yes, install a new clockspring. Restore the vehicle. Clear DTCs and retest the system. If no, go to next step.

  7. 7) Check Signal Circuit For A Short To Voltage

    Key off. Disconnect the PCM body harness connector C1381A. Key on. Measure the voltage between PCM body harness connector C1381A terminal No. 31 and ground. See CONTROL MODULE CONNECTOR IDENTIFICATION . Is the voltage reading 0 volt? If yes, install a new PCM. Restore the vehicle. Clear DTCs and retest the system. If no, repair short to voltage short. Restore the vehicle. Clear DTCs and retest the system.

  8. 8) Check Shorted Command Switch

    Remove horn pad. Disconnect 3-way speed control switch harness connector. Is the voltage reading 6.58-6.78 volts? If yes, install a new speed control switch assembly. Restore the vehicle. Clear DTCs and retest the system. If no, go to next step.

  9. 9) Check Clockspring

    Disconnect clockspring connector. Is the voltage reading 6.58-6.78 volts? If yes, install a new clockspring. Restore the vehicle. Clear DTCs and retest the system. If no, go to next step.

  10. 10) Check Signal Circuit For A Short To Ground

    Key off. Disconnect the PCM body harness connector C1381A. Disconnect the speed control switch electrical connector. Measure the resistance between PCM body harness connector C1381A terminal No. 31 and ground. See CONTROL MODULE CONNECTOR IDENTIFICATION . Is the resistance greater than 10,000 ohms? If yes, install a new PCM. Restore the vehicle. Clear DTCs and retest the system. If no, repair short to ground in signal circuit. Restore the vehicle. Clear DTCs and retest the system.

  11. 11) Check Fuse

    Key off. Remove fuse No. 37 (15-amp). Is fuse okay? If yes, go to next step. If no, install a new fuse. Restore the vehicle. Clear DTCs and retest the system.

  12. 12) Check Continuity From Fuse To Horn Pad

    Remove horn pad. Disconnect 5-way speed control switch harness connector. Measure resistance between non-power side of fuse and terminal "C" of clockspring in column. See Figure. Is the resistance less than 75 ohms? If yes, go to next step. If no, go to step  16).

  13. 13) Check Speed Control Switch

    Measure resistance between terminals "A" and "C" on horn assembly harness. Press ON switch. Is the resistance less than 5 ohms? If yes, go to next step. If no, install a new speed control switch assembly. Restore the vehicle. Clear DTCs and retest the system.

  14. 14) Check Signal Control Circuit For An Open

    Measure the resistance between the PCM body connector C1381A terminal No. 31 and speed control switch harness connector signal circuit terminal "A". See CONTROL MODULE CONNECTOR IDENTIFICATION . Is the resistance less than 5 ohms? If yes, go to next step. If no, repair open in signal control circuit. Restore the vehicle. Clear DTCs and retest the system.

  15. 15) Check Clockspring Circuit

    Measure resistance between speed control switch harness connector terminal "C" and terminal No. 5 of clockspring side of connector. Is the resistance less than 5 ohms? If yes, install a new PCM. Restore the vehicle. Clear DTCs and retest the system. If no, install a new clockspring. Restore the vehicle. Clear DTCs and retest the system.

  16. 16) Check Resistance Across Clockspring

    Disconnect clockspring connector. Measure resistance between terminal "C" and terminal No. 5 on clockspring connector column side. Is the resistance less than 5 ohms? If yes, install a new CJB. Restore the vehicle. Clear DTCs and retest the system. If no, install a new clockspring. Restore the vehicle. Clear DTCs and retest the system.

  17. 17) Check Ground At Switch

    Remove horn pad. Disconnect speed control switch harness connector. Measure voltage between terminals "B" and "C" of the clockspring connector in column. See Figure. Does voltage reading indicate B+? If yes, install a new speed control switch assembly. Restore the vehicle. Clear DTCs and retest the system. If no, go to next step.

  18. 18) Check Clockspring For Open

    Key off. Disconnect clockspring connector. Measure resistance between terminal "B" and terminal No. 3 on clockspring side of connector. Is the resistance less than 5 ohms? If yes, go to next step. If no, install a new clockspring. Restore the vehicle. Clear DTCs and retest the system.

  19. 19) Check Signal Return Circuit For An Open

    Disconnect the PCM body harness connector C1381A. Measure the resistance between the PCM body harness connector C1381A terminal No. 24 and the speed control switch return circuit. See CONTROL MODULE CONNECTOR IDENTIFICATION . Is the resistance less than 5 ohms? If yes, install a new PCM. Restore the vehicle. Clear DTCs and retest the system. If no, repair open in signal return circuit. Restore the vehicle. Clear DTCs and retest the system.
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