MIRROR OPERATION
The output stages and memory storage of mirror positions is handled by the respective
door modules. The positioning of the mirrors is signaled from the driver’s door switch
block/module. The signal passes over the P-Bus to the passenger’s door module.
The memory/recall for the driver’s mirror comes directly into the door module from the
memory switch. The operation for the passenger’s side mirror is carried out over the P-Bus
from the driver’s door module to the passenger’s door module.
The memory positions are stored in each respective module. The memory position is rec-
ognized by the feedback potentiometers located on each mirror motor.
The reverse gear tilt feature for the passenger’s mirror is signaled from the GM III, over the
P-bus, when reverse is selected and the mirror switch is set for the driver’s side.
Mirror heating is controlled by each respective door module. The GM III receives the out-
side temperature from the IKE and passes it to the door modules. The “ON” time for mirror
heating is adjusted based on the outside temperature.
A pulsed heating cycle is used for the mirrors based on the outside temperature.
ZKE -55
Temperature<-10OC -10 to 0OC 0 to 15OC 15 to 25OC >25OC
ON - duration 100% 75% 50% 25% 5%
SEAT OPERATION
Each motor for seat adjustment contains a micro-processor (called a Ripple Counter) that
receives a digital signal from the seat control module for motor activation. The motors are
connected to KL 30 and KL 31 and respond to the signals generated by the seat module
when seat movement is requested. The seat adjustment switch provides ground input sig-
nals to the module when seat movement is desired. The module processes these input sig-
nals and sends output signals to the seat motor processors. The seat motor processors
activate the motors and the seat moves to the desired point.
The circuitry of the Ripple Counter detects the motor activation current. As the armature
segments of the motor rotate passed the brushes, the current flow rises and falls produc-
ing a ripple effect. The peaks of these ripples are counted and stored in the Ripple Counter
module. The memory function of the seat module uses this ripple count instead of feed-
back potentiometers to memorize and recall seat positions.
RIPPLE COUNT RECOGNITION
When the seat is installed and the battery is connected, the ripple counter uses the initial
position of the motors as the “Zero Position”. Any movement from this point is counted as
“+” or “-” pulses as the motors move in either direction. The pulse position of the motors
is stored in the seat module, in an EEPROM, before the ZKE goes into its “Sleep Mode”.
This prevents the position recognition from being lost. If the battery is disconnected before
the 16 minute sleep mode activation, the memory positions of the seat will be lost and
reprogramming will be required.
ZKE -57
