B2276

DTC B2276 Door Lock Motor/Mirror Heater Flt DCM - L:

CIRCUIT DESCRIPTION
The LH Door Control Module (LDCM) provides the LH door lock and LH heated mirror control output functions. When the LDCM detects an active door LOCK or UNLOCK command from either the LH window switch, or from a LOCK or UNLOCK message sent on the serial data line by the RH Door Control Module (RDCM), the LDCM will LOCK or UNLOCK the LH door. The LDCM accomplishes this by applying a ground or voltage to CKT 294 and CKT 295 depending on which command (LOCK or UNLOCK) was requested. The LDCM also controls the LH heated mirror functions by supplying a ground and voltage to the LH heated mirror. When the LDCM receives a message on the serial data line indicating the rear defogger was turned ON, the LDCM will activates the LH heated mirror by applying voltage to CKT 267. The LDCM monitors the voltage level and the amount of current draw on the LH door lock control circuit and the LH heated mirror control circuit. If the voltage level and/or current draw in either circuits are not within the acceptable range, a malfunction is present and a DTC will set.

CONDITIONS FOR SETTING THE DTC
^ The LDCM detects a high current or a short to voltage condition in the LH door lock control circuit when the LH door lock is activated
^ The LDCM detects a high current or short to voltage condition in the LH heated mirror control circuit when the LH heated mirror is activated (rear window defogger is ON).
^ Condition must be present for 150 ms.
^ The LDCM detects a voltage drop of 5 volts or more at battery 2 when the LDCM activates the LH door lock or the LH heated mirror.

ACTION TAKEN WHEN THE DTC SETS
^ Stores a history DTC B2276 in the LDCM 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.
^ Disables all LH door lock or LH heated mirror functions depending on which circuit the LDCM detected the malfunction.

CONDITIONS FOR CLEARING THE DTC
^ The rear window defogger must be turned ON.
^ The LDCM no longer detects a high current or short to voltage condition in the LH door lock control circuit.
^ The LDCM no longer detects a high current or short to voltage condition in the LH heated mirror control circuit.
^ The LDCM no longer detects a voltage drop of 5 volts or more at battery 2 when the LDCM applies the LH door lock or LH heated mirror.
^ Use the IPC clearing DTCs feature.
^ Use a scan tool.

DIAGNOSTIC AIDS
^ The following conditions may cause an intermittent malfunction:
- There is an intermittent short to voltage in CKT 267, CKT 294 or CKT 295.
- The LH door lock motor or LH heated mirror is shorted internally.
^ If the LDCM detects a malfunction in the LH door lock or LH heated mirror control system, the LDCM will disable the system that the malfunction was detected in.
^ Using a scan tool, select LDCM Data display and monitor battery 2 voltage while cycling the door locks. If battery 2 voltage drops more than 5 volts, then the LH door lock control circuit must be checked for a short to ground. Sense LDCM also monitors the voltage level in the LH heated mirror control circuit, this test can be applied to the heated mirror system.
^ 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 if the malfunction is located in the LH heated mirror circuit or the LH door lock circuit.
3. This test checks if the LDCM is sending the correct supply voltage to the LH heated mirror.
4. This test checks if the LDCM is sending the correct supply voltage to the LH door lock.