Circuit Description
The LH Door Control Module (LDCM) receives both vertical and horizontal position signals from the LH mirror. These signals are used by the LDCM for memory recall functions to determine the vertical and horizontal position of the LH mirror. The LDCM commands the mirror memory settings based upon the voltage level the LDCM receives back from the vertical and horizontal position sensors. The LDCM provides a 5 volt supply, a signal, and a ground to both of the position sensors. The position sensors are variable resistors which the LDCM monitors the voltage level across. When a memory setting is recalled, the LDCM will command the LH mirror motor in the appropriate direction until both the vertical and horizontal position sensors are within the voltage range stored in memory. The LDCM also monitors the LH mirror vertical and horizontal position sensor 5 volt supply circuit and can determine if the voltage level received is out of range. If the voltage level is out of range, then a malfunction is present and a DTC will set.
Conditions for Setting the DTC
| • | The LDCM detects the LH mirror vertical and horizontal position sensor supply voltage range under 4.0 volts or over 5.2 volts. |
| • | Condition must be present for 2 seconds. |
Action Taken When the DTC Sets
| • | Stores a history DTC B2286 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. |
Conditions for Clearing the DTC
| • | The LDCM detects the LH mirror vertical and horizontal position sensor supply voltage range between 4.0-5.2 volts for longer than 2 seconds. |
| • | Use the IPC clearing DTCs feature. |
| • | Use a scan tool. |
Diagnostic Aids
| • | The following conditions may cause an intermittent malfunction: |
| - | There is an intermittent open or short (to ground or voltage) in CKT 788, CKT 786, CKT 784, or CKT 1251. |
| - | The LH mirror vertical or horizontal sensor is shorted internally. |
| • | If the LDCM is unable to determine the correct vertical or horizontal position, manual power mirror functions will still operate, but the LDCM will not be able correctly recall the position of the mirror when the memory button is pressed. |
| • | Using a scan tool, select LDCM Data display and monitor the mirror position sensor data. Move the power mirror vertically and horizontally while monitoring the position sensor data. This checks if the mirror position sensor supply voltage is within range in different positions. |
| • | 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 . |
Test Description
The numbers below refer to the step numbers on the diagnostic table:
-
This test checks the position sensor reference voltage using a scan tool. Normal mirror position sensor reference voltage range is between 4.0-5.2 volts.
-
This test checks if the LDCM is sending the correct supply voltage to the LH mirror. The supply voltage measured must be between 4.0-5.2 volts.
-
This test checks for an open or short to voltage in CKT 1251 or in the LDCM internal ground circuit.
Step | Action | Value(s) | Yes | No |
|---|---|---|---|---|
1 | Were you sent here from the Power Door Diagnostic System Check? | -- | ||
Using a scan tool, select LDCM data display and monitor position sensor reference data. Does the scan tool display position sensor reference voltage within the specified range? | 4.0-5.2 V | |||
Is the voltage within the specified range? | 4.0-5.2 V | |||
At the LH mirror connector C2 (harness side), measure the voltage between terminals A and C. Is the voltage within the specified range? | 4.0-5.2 V | |||
5 | Check for an open or short (to ground or voltage) in CKT 788. Was a problem found and repaired? | -- | ||
6 | Check for an open or short to voltage in CKT 1251. Was a problem found and repaired? | -- | ||
7 | Replace the LH mirror assembly. Refer to Outside Rearview Mirror Replacement . Is the replacement complete? | -- | -- | |
8 |
Is the replacement complete? | -- | -- | |
9 | Check the mirror supply circuit for an intermittent malfunction. Refer to Diagnostic Aids. Was a problem found and repaired? | -- | ||
10 |
Does DTC B2286 set as history? | -- | System OK | |
11 |
Is the repair complete? | -- | -- |
