B2144

DTC MMM B2144-B2151:

CIRCUIT DESCRIPTION
Each position sensor is a potentiometer, whose resistance varies as the mirror is moved. For all memory functions, the Memory Mirror Module (MMM) receives an input from each mirror position sensor. For Memory Set, the MMM stores the current voltages across the position sensors. For Memory Recall and Memory Exit, the MMM moves the mirrors until the voltage across each position sensor matches the voltage stored.


CONDITIONS FOR SETTING THE DTC
^ These DTCs will set only if DTC MSM B1982 or DTC MSM B1983 is not current.
^ The MMM will set the appropriate DTC any time it detects that the sensor input voltage is out of range. When the MMM detects that a mirror sensor input voltage is less than 0.25 volts, it will set the shorted to ground DTC. When the MMM detects that a mirror sensor input voltage is equal to or greater than 4.75 voltsit will set the shorted to battery voltage DTC.

ACTION TAKEN WHEN THE DTC SETS
The MMM will disable the motor in the direction that the DTC is set during memory recall and easy exit operations. The motor is enabled during manual positioning.

CONDITIONS FOR CLEARING THE MIL/DTC
The MMM does not detect the Out of range condition during the last monitoring cycle.

DIAGNOSTIC AIDS
^ If multiple mirror position sensor DTCs are set, check CKT 934 (LT GRN/BLK) for an open or short, and check CKT 939 (RED/BLK) for an open.
^ If one mirror position sensor DTC is set, check me wiring from the position sensor to the MMM. If OK, replace the suspect mirror position sensor. Mirror position sensor wiring includes:
- LH Vertical: CKT 784 (DK URN)
- LH Horizontal: CKT 786 (GRY)
- Passenger Vertical: CKT 787 (B RN)
- Passenger Horizontal: CKT 785 (LT BLU/BLK)