Wiper/Washer System Components
The Wiper/Washer System consists of the following components:
• | Windshield wiper/washer switch |
• | Underhood Electrical Center (UEC) |
• | Steering Wheel Module (SWM) |
• | Rear Electrical Center (REC) |
• | Windshield washer fluid pump |
• | Windshield washer fluid level switch |
Refer to
Master Electrical Component List .
Power and Grounds
The underhood electrical center (UEC) is a central module in the front of the car placed close to the battery, It consists of a fuse box, a relay box and a control module which communicates on LS CAN. The UEC controls all the functions of the front and
rear wipers. The UEC gets power directly from the battery. There are two internal relays that are controled by the module portion of the UEC based off the messages it recieves from the wiper switch in the steering wheel module (SWM). When activated the wiper
stalk does not stay in a detented position but returns to a neutral position . The system is turned off by pushing the switch in the other direction.
Modes of Operation
The normal wiper system function positions are as follows:
• | Wiper blade service position, With the ignition OFF but key in "O" position |
Wiper Speeds
All the wiper speeds are controled by LS CAN messaging from the SWM to the UEC. The UEC activates the wiper relays to obtain the desired wiper speed.
Moisture Sensitive Wipers
The rain sensor is connected to the UEC by a UART data line. With moisture sensitive wipers if intermittent wipers are selected the UEC decides the wiper speed depending on the amount of rain measured by the rain sensor. If the rain sensor fails the systems
operates like an ordinary delay system without moisture sensitive wipers.
Front Washer Operation
If the SWM requests to activate the front washers a LS CAN message is sent to the UEC, the UEC then activates the washer pump and the wipers. If the vehicle is moving below a certain speed the wipers are activated a bit later than the washers. The amount
of wiper movements depends on how long the wiper switch is held in the wash position.
Front washers
The front windshield washers are controlled by the SWM sending a LS CAN message to the UEC . The UEC then activates the front washer pump and the wipers. The amount of wash and wiper movement depend on how long the washer switch has been held on.