B2339–HORN SWITCH STUCK — SCCM





For a complete wiring diagram Refer to Section 8W.

Theory of Operation


The Horn Switch connects to the Steering Column Control Module (SCCM) via a serial sub-bus called the LIN bus. The SCCM monitors the Horn Switch status. When the switch status changes (switch is pressed or released), the SCCM processes the request and broadcasts it on the CAN B Bus where it is read and processed by the Front Control Module (FCM).


  • When Monitored:

    Continuously.

  • Set Condition:

    If the Steering Column Control Module (SCCM) senses that the Horn Switch is in the Set position for more than 50 seconds.


Possible Causes
  
(X3) HORN SWITCH SIGNAL CIRCUIT SHORTED TO (X903) HORN SWITCH RETURN CIRCUIT
  
(X3) HORN SWITCH SIGNAL CIRCUIT SHORTED TO GROUND
  
HORN SWITCH
  
STEERING COLUMN CONTROL MODULE (SCCM)
  



Diagnostic Test

1.TEST FOR INTERMITTENT CONDITION

NOTE: If DTC P0562 BATTERY VOLTAGE LOW or DTC P0563 BATTERY VOLTAGE HIGH is active along with this DTC, diagnose and repair the battery voltage related DTC first.





Does the scan tool display DTC B2339 HORN SWITCH STUCK active?

Yes
  • Go To 2


No
  • The conditions necessary to set this DTC are not present at this time. Using the wiring diagram/schematic as a guide, inspect the wiring and connectors. In addition, wiggle test the wiring and connectors while monitoring the scan tool data relative to this circuit. Look for the data to change or for the DTC to set as active during the wiggle test. Repair as necessary.
  • Perform BODY VERIFICATION TEST - VER 1. (Refer to 8 - ELECTRICAL/ELECTRONIC CONTROL MODULES - STANDARD PROCEDURE).

2.TEST THE HORN SWITCH






Does the ohmmeter reading indicate continuity when the switch is pressed and no continuity when the switch is released?

Yes
  • Go To 3


No

3.CHECK THE (X3) HORN SWITCH SIGNAL CIRCUIT FOR A SHORT TO THE (X903) HORN SWITCH RETURN CIRCUIT






Is the resistance below 10k ohms?

Yes


No
  • Go To 4

4.CHECK THE (X3) HORN SWITCH SIGNAL CIRCUIT FOR A SHORT TO GROUND





Is the resistance below 10k ohms?

Yes


No