B2253

DTC B2253 Key Cylinder Switch Fault - DCM - Right:

CIRCUIT DESCRIPTION
The RH door key switch circuit provides input to the RH Door Control Module (RDCM) when the RH door key switch is rotated the UNLOCK position. This input allows the RDCM to detect when the door is unlocked. This information is sent on the serial data line and used by other systems to execute certain functions (UTD, Illuminated entry, hatch release, etc.). The RDCM provides both power and ground to the RH door key switch. When the RH door key switch is rotated the UNLOCK position, a ground is supplied through the RH door key switch to the RH door key switch input which is pulled low. When the RDCM detects low voltage on the RH door key switch input, the RDCM will UNLOCK the passenger door and will also send a message on the serial data line to the LH Door Control Module (LDCM) to UNLOCK the driver door. The RDCM monitors the RH door key switch input circuit and determines how long a ground (switch activated) has been applied. If the ground is applied for longer than expected, a malfunction is present and a DTC will set.

CONDITIONS FOR SETTING THE DTC
^ The RDCM detects a low voltage level (short to ground) at the RH door key switch input circuit.
^ Condition must be present for 20 seconds.

ACTION TAKEN WHEN THE DTC SETS
^ Stores a history DTC B2253 in the RDCM memory.
^ This DTC can only be set as a history code even if the malfunction is current.
^ No driver warning message will be displayed for this DTC.

CONDITIONS FOR CLEARING THE DTC
^ The RDCM no longer detects a low voltage level (short to ground) at the RH door key switch input circuit for longer than 20 seconds.
^ Use the IPC clearing DTCs feature.
^ Use a scan tool.

DIAGNOSTIC AIDS
^ The following conditions may cause an intermitten malfunction:
- There is an intermittent short to ground in the RH door key switch input circuit (CKT 265).
- The RH door key switch is shorted to ground internally or is sticking.
- The RH door key switch was activated for longer than 20 seconds.
^ Using a scan tool, select RDCM inputs and monitor the RH door key switch status. If the scan tool displays ACTIVE, disconnect the RH door key switch and check if the RH door key switch status changes to INACTIVE. If the status changed, then replace the RH door key switch. If the status did not change, then check CKT 265 for a short to ground.
^ If the DTC does not reset after the code is cleared, then the problem may be intermittent. Perform the tests shown while moving related wiring and connectors. This can often cause the malfunction to occur. Refer to Intermittents and Poor Connections. Testing and Inspection

TEST DESCRIPTION
The numbers below refer to the step numbers on the diagnostic table:
2. This test determines the status of the RH door key switch using a scan tool. The scan tool will display the RH door key switch status as ACTIVE (button pressed) and INACTIVE (button released).
3. This test checks if the RH door key switch is shorted to ground or stuck. If the RH door key switch status changes from ACTIVE to INACTIVE when the RH door key switch is disconnected, then the RH door switch assembly must be replaced.