Blind Spot Monitoring System - Operation

BLIND SPOT MONITOR SYSTEM

The Blind Spot Monitor (BSM) system is active only when the ignition switch is in the ON or START positions, the transmission gear selector lever is in the DRIVE or NEUTRAL position and the vehicle speed is greater than 10 kilometers-per-hour (6 miles-per-hour). In vehicles equipped with this option, the system is enabled from the factory as a default. The system can be manually disabled and enabled by the vehicle operator using the customer programmable features option of the optional Electronic Vehicle Information Center (EVIC) in the instrument cluster.

The BSM system provides another feature called Rear Cross Path (RCP). The RCP feature is active only when the gear selector is in the reverse position. The RCP feature is intended to aid the driver when backing out of parking spaces where vision of oncoming vehicles may be blocked. The host vehicle must proceed slowly and cautiously out of the parking space until the rear end of the vehicle is exposed. The RCP system will then have a clear view of the cross traffic and if an on coming vehicle is detected, alert the driver. The RCP monitors the rear detection zones on both sides of the vehicle, for objects that are moving toward the side of the vehicle with a minimum speed of 1 to 2 mph (1 km/h to 3 km/h), to objects moving a maximum of 10 mph (16 km/h), such as in parking lot situations.

The microprocessor based blind spot monitor module is the central component of the BSM system. It receives and analyzes data from the sensors, calculates and communicates the proper information to the Driver/Passenger door module to illuminate the display, performs system diagnostics, and communicates with other electronic modules in the vehicle or with a diagnostic scan tool over the Controller Area Network (CAN) data bus. The module operates on battery voltage received through a fuse in the Totally Integrated Power Module (TIPM), and is grounded through a take out and eyelet terminal of the body wire harness that is secured by a screw to the body sheet metal.

Two BSM radar sensors in the rear bumper fascia allow the blind spot monitor system to locate and identify nearby obstacles. The width of the BSM detection zone covers one lane over on both side of the vehicle, approximately 13ft (4.0m). The length of the BSM zone starts at the outside rear view mirror and extends approximately 15ft (4.5m) from the edge of the rear bumper.

The BSM display units, located within the side view mirrors, provide the vehicle operator with a visual warning indicating that an object has been detected within one of the vehicles detection zones. The BSM display ICON is illuminated immediately if an object of interest is in the detection zone and meets the warning criteria. However, the BSM system will not illuminate the ICON if the object of interest from the rear of the zone and passes the host vehicle at a speed greater that 31mph (50kph), or enters the detection zone from the front of the zone and remains in the zone for less than 1.5 seconds or passes through the zone with a relative speed greater than 12mph (20kph), or if the target vehicle passes the host vehicle in the opposite direction.

The BSM audible alert, is a single chime tone that can also be enabled. The chime tone is only sounded when the turn signal is activated and an object of interest is in the detection zone on the same side and meets the warning criteria. The chime tone is not active during normal driving conditions unless the turn signal is activated. The BSM system also sends a radio mute signal over the CAN data bus to the radio when the chime tone is activated. This request signal activates the radio mute function while the chime tone is sounded, approximately 2 to 3 seconds, then resumes normal radio function. The audible alert my also be deactivated if the operator prefers using the driver preferences within the EVIC. The BSM system can be configured for lights and chime, lights only, and system off.

The RCP function uses the same BSM icon and audible chime. However, the RCP function always combines the BSM display with the audible chime if an object is detected within the RCP detection zone. The BSM icon is illuminated on the side where the object is detected and a rapid repeating short chime tone is sounded. The audible chime can not be deactivated in the RCP function.

When the BSM module monitors a problem in any of the system circuits or components, it stores a fault code or Diagnostic Trouble Code (DTC) in its memory circuit, sends an electronic message to the instrument cluster, and a SERVICE BLIND SPOT SYSTEM or BLIND SPOT SYSTEM TEMPORARILY UNAVAILABLE textual message is displayed in the EVIC display.

The hardwired circuits between components related to the blind spot monitor system may be diagnosed using conventional diagnostic tools and procedures. Refer to the appropriate wiring information. The wiring information includes wiring diagrams, proper wire and connector repair procedures, details of wire harness routing and retention, connector pin-out information and location views for the various wire harness connectors, splices and grounds.

However, conventional diagnostic methods will not prove conclusive in the diagnosis of the blind spot monitor system or the electronic controls or communication between modules and other devices that provide some features of the system. The most reliable, efficient, and accurate means to diagnose the blind spot monitor system or the electronic controls and communication related to BSM system operation requires the use of a diagnostic scan tool. Refer to the appropriate diagnostic information.