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Cross Traffic Alert (CTA) System




Blind Spot Monitoring

Cross Traffic Alert (CTA) System

NOTE: The BLIS(TM) and CTA system both utilize the SOD-L, SOD-R and the exterior mirror BLIS(TM)/CTA LEDs.

The CTA system is an alert feature that assists the driver in backing out of a front-in parking space. When the transmission is in REVERSE (R) the CTA system is active. The driver is warned of an approaching vehicle when an audio alert chime from the parking aid speaker sounds, the right or left exterior mirror BLIS(TM)/CTA amber LED flashes, and the Instrument Panel Cluster (IPC) message center displays "VEHICLE COMING FROM RIGHT or VEHICLE COMING FROM LEFT" to warn the driver from which direction vehicles are approaching.

The CTA system detects a vehicle approaching up to 14 m (45 ft) away (approximately the width of five parking spaces). The radar coverage of the SOD-L and SOD-R decreases when vehicles and objects are in close proximity from the rear side of the vehicle. Backing out of parking spots slowly increases the radar sensor coverage in close proximity situations. The CTA system coverage also decreases when parking at shallow angles, which is described in the Owner's Literature.

The CTA system utilizes the same SOD-L and SOD-R as the BLIS(TM).

The CTA system cannot detect stationary vehicles, humans, animals or objects such as fences, guard rails or trees. The system does not function when the transmission is in DRIVE (D) or NEUTRAL (N).

The CTA system has some detection limitations due to the nature of the radar technology for the SOD-L and SOD-R. There can be certain instances where vehicles entering and exiting the blind spot zone may not be detected. The circumstances that may cause non-detection are:

- Debris build up on the rear quarter panel fascias
- The rear quarter panel of the vehicle is obstructed or partially obstructed by an adjacently parked vehicle or object
- Approaching vehicle passing at speeds greater than 24 km/h (15 mph)
- Severe weather conditions
- Driving in reverse (R) faster than 5 km/h (3 mph)
- Backing out of an angled parking spot

The CTA system can be turned off by selecting the CTA system ON/OFF function in the message center. The CTA system is turned off in the IPC message center by selecting the CTA system with the SETUP switch for the message center and selecting the system on or off with the RESET switch. The message "CTA SYSTEM OFF" is displayed in the message center. The CTA system cannot be deactivated in the message center when the transmission is in REVERSE (R). The system is reactivated on the next ignition cycle.

The CTA system can be disabled permanently (even after an ignition cycle) by using a scan tool. When using the scan tool disable function in the programmable parameters menu, the CTA system remains disabled until it is reactivated using the scan tool. When the system is disabled the IPC message center displays "CTA DISABLED". A system fault occurs if the CTA system is not disabled in both the SOD-L and the SOD-R.

There are some system faults that set DTCs which are logged in the SOD-L or SOD-R. These DTCs that are logged can set a message in the IPC message center that displays "CTA SYSTEM FAULT". There are also some symptom based faults that do not set a DTC and only the message "CTA SYSTEM FAULT" is displayed in the IPC message center. This type of fault is resolved with the use of the symptom chart. GO to Symptom Chart Blind Spot Monitoring

Blocked Sensor

An excessive build up of materials on the left and/or right rear quarter panel fascias, such as mud or snow, can cause the BLIS(TM) or CTA system functionality to degrade. Heavy rain can have the same effect. If the system is in a blocked state, the radar misses targets, but still counts them. After approximately 4 counted/missed targets, the system sends a "BLOCK SENSOR" and "BLIND SPOT NOT AVAILABLE" or "CTA NOT AVAILABLE" message to the cluster. If the blocked condition is determined by either system the message center displays "BLIND SPOT NOT AVAILABLE" or "CROSS TRAFFIC NOT AVAILABLE" and the appropriate left and/or right exterior mirror BLIS(TM)/CTA LED illuminates.

The message center warning can be cleared by the driver but the exterior mirror BLIS(TM)/CTA LED remains illuminated. Once the blockage is removed, the system requires some drive time and a system detection of at least two vehicle objects prior to realizing it is unblocked. The ignition key can also be cycled off to clear the blocked state. However, if the blockage is still present after the key cycle, the system senses again that it is blocked and the blocked message is observed after driving the vehicle.

There are several conditions that cause the BLIS(TM) or CTA system to not operate correctly or prevent the system from activation. These conditions include:

- Ice, snow or soil adhering to the rear quarter panel surface around the radar sensor.
- Adverse weather conditions such as rain or snow or under conditions where water is sprayed.

The rear quarter panels and rear bumper cover should be cleaned of mud, snow, ice or any obstruction to restore normal operation.

Network Communication

While there are numerous messages internal to the SOD-L and SOD-R, the following messages are utilized by the BLIS(TM) and CTA system.

BLIS(TM) and CTA System Network Communication Messages

NOTE: Both the Medium Speed Controller Area Network (MS-CAN) and the High Speed Controller Area Network (HS-CAN) are used for intermodule communication. A gateway message is transferred from one network to another network through the IPC. Refer to Module Communications Network Testing and Inspection for network communication information.