P0572-BRAKE SWITCH 1 STUCK ON





For a complete wiring diagram Refer to Section 8W.


  • When Monitored:

    Ignition on.

  • Set Condition:

    When the PCM recognizes Brake Switch No.1 is mechanically stuck in the low/on position. Two Trip Fault. Three Global Good Trips to Clear.


Possible Causes
  
(B15) BRAKE SIGNAL 1 CIRCUIT SHORTED TO GROUND
  
(B16) BRAKE SIGNAL 2 CIRCUIT OPEN
  
STOP LAMP SWITCH
 
PCM
  

Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. (Refer to 9 - ENGINE - DIAGNOSIS AND TESTING).



Diagnostic Test

1.ACTIVE DTC

NOTE: Verify battery voltage is greater than 10 volts.





NOTE: It may be necessary to drive the vehicle to meet the conditions to set this DTC, try to repeat the conditions in which the fault originally set by reviewing the Freeze Frame data.



Is the DTC Active or Pending at this time?

Yes
  • Go To 2


No

2.STOP LAMP SWITCH







Does the resistance change from below 5.0 ohms to an open circuit?

Yes
  • Go To 3


No

3.(B15) BRAKE SIGNAL 1 CIRCUIT SHORTED TO GROUND







Is the resistance below 100 ohms?

Yes


No
  • Go To 4

4.(B16) BRAKE SIGNAL 2 CIRCUIT OPEN


CAUTION: Do not probe the PCM harness connectors. Probing the PCM harness connectors will damage the PCM terminals resulting in poor terminal to pin connection. Install Miller Special Tool #8815 to perform diagnosis.




Is the resistance below 5.0 ohms?

Yes
  • Go To 5


No

5.PCM

NOTE: Before continuing, check the PCM harness connector terminals for corrosion, damage, or terminal push out. Repair as necessary.




Were there any problems found?

Yes


No