The driver door module (DDM) and passenger door module (PDM) receive mirror position signals from the mirror horizontal and vertical position sensors. These signals are used by the door modules for memory recall functions of the driver and passenger mirrors. The door modules command the mirror memory settings based upon the voltage level received back from the position sensors. Each door module provides a 5 volt supply, a signal, and ground circuit for each of the position sensors. The horizontal and vertical position sensors are variable resistors that the door modules monitor voltage levels across. When a memory setting is recalled, the door modules command the mirror motors in the appropriate directions until the stored position sensor voltage levels are achieved. The DDM and PDM monitor the signal circuits to determine if the voltage level is out of range.

Battery voltage must be between 9-16 volts.

B1580 08

An improper voltage level is seen on the horizontal position sensor signal circuit.

B1590 08

An improper voltage level is seen the vertical position sensor signal circuit.

Memory mirror recall functions are suspended as long as the fault is present.

Schematic Reference

Outside Rearview Mirror Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Outside Mirror Description and Operation

Electrical Information Reference

Scan Tool Reference

Control Module References for scan tool information

1. Ignition OFF, disconnect the X3 harness connector at the appropriate door module.
2. Ignition ON, verify a test lamp does not illuminate between the following circuit terminals and ground:

•	5-volt reference circuit terminal 7

•	Signal circuit terminal 2

•	Signal circuit terminal 3

•	Low reference circuit terminal 6

⇒	If the test lamp illuminates, test the appropriate circuit for a short to voltage.

3. Ignition OFF, test for infinite resistance between the following circuits and ground:

•	5-volt reference circuit terminal 7

•	Signal circuit terminal 2

•	Signal circuit terminal 3

•	Low reference circuit terminal 6

⇒	If less than the specified value, test the appropriate circuit for a short to ground.

4. Test for 4K-7K ohms between the 5-volt reference circuit terminal 7 and the low reference circuit terminal 6.

⇒	If not within the specified range, test the 5-volt reference circuit and the low reference circuit for an open/high resistance. If the circuits test normal, test or replace the rearview mirror.

5. Test for 1K-7K ohms between the 5-volt reference circuit terminal 7 and the signal circuit terminal 2.

⇒	If not within the specified range, test the signal circuit for an open/high resistance. If the circuits test normal, test or replace the rearview mirror.

6. Test for 1K-7K ohms between the 5-volt reference circuit terminal 7 and the signal circuit terminal 3.

⇒	If not within the specified range, test the signal circuit for an open/high resistance. If the circuits test normal, test or replace the rearview mirror.

7. If all circuits test normal, replace the door module.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.