GM Service Manual Online
For 1990-2009 cars only

The vehicle may have a Side Blind Zone Alert (SBZA) system. Read this entire section before using the system.

The SBZA system operates on a radio frequency subject to Federal Communications Commission (FCC) Rules and with Industry Canada.

This device complies with Part 15 of the FCC Rules. Operation is subject to the following two conditions:

  1. This device may not cause harmful interference.
  2. This device must accept any interference received, including interference that may cause undesired operation.

This device complies with RSS-310 of Industry Canada. Operation is subject to the following two conditions:

  1. This device may not cause harmful interference.
  2. This device must accept any interference received, including interference that may cause undesired operation.

Frequency of operation: 24.05GHz - 24.25GHz

Field Strength: Not greater than 2.5V/m peak (0.25V/m average) at a distance of 3m

The manufacturer is not responsible for any radio or TV interference caused by unauthorized modifications to this equipment. Such modifications could void the user's authority to operate the equipment.

Caution: SBZA is only a lane changing aid and does not replace driver vision. SBZA does not detect:

   • Vehicles outside the side blind zones which may be rapidly approaching.
   • Pedestrians, bicyclists, or animals.
Failure to use proper care when changing lanes may result in damage to the vehicle, injury, or death. Always check the outside and rearview mirrors, glance over your shoulder, and use the turn signal before changing lanes.

When the system detects a vehicle in the side blind zone, amber SBZA displays will light up in the side mirrors. This indicates that it may be unsafe to change lanes. Before making a lane change, always check the SBZA display, check the outside and rearview mirrors, look over your shoulder for vehicles and hazards, and use the turn signal.


Object Number: 1761977  Size: B3

SBZA Detection Zones

The SBZA sensor covers a zone of approximately one lane over from both sides of the vehicle, 11 ft. or 3.5 m. This zone starts at each side mirror and goes back approximately 16 ft. (5.0 m). The height of the zone is approximately between 1.5 ft. (0.5 m) and 6 ft. (2.0 m) off the ground.

The SBZA detection zones do not change if the vehicle is towing a trailer. So be extra careful when changing lanes while towing a trailer.

How the System Works

Left Side Mirror Display


Object Number: 1761980  Size: A1

Right Side Mirror Display


Object Number: 1761982  Size: A1

When the vehicle is started, both outside mirror displays will briefly come on to indicate that the system is operating. While driving forward, the left or right side mirror SBZA display will light up if a vehicle is detected in that blind zone. If you activate a turn signal and a vehicle has been detected on the same side, the SBZA display will flash to give you extra warning not to change lanes.

SBZA displays do not come on while the vehicle is approaching or passing other vehicles. At speeds greater then 20 mph (32 km/h), SBZA displays may come on when a vehicle you have passed remains in or drops back into the detection zone.

SBZA can be disabled through the Driver Information Center (DIC). See Driver Information Center (DIC) for more information. If the SBZA is disabled by the driver, the SBZA mirror displays will not light up during normal driving.

When the System Does Not Seem To Work Properly

Occasional missed alerts can occur under normal circumstances and will increase in wet conditions. The system does not need to be serviced due to an occasional missed alert. The number of missed alerts will increase with increased rainfall or road spray.

If the SBZA displays do not light up when the system is on and vehicles are in the blind zone, the system may need service. Take the vehicle to your dealer/retailer.

SBZA is designed to ignore stationary objects; however, the system may occasionally light up due to guard rails, signs, trees, shrubs, and other stationary objects. This is normal system operation, the vehicle does not need service.

SBZA does not operate when the left or right corners of the rear bumper are covered with mud, dirt, snow, ice, slush, or in heavy rainstorms. For cleaning instructions, see Washing Your Vehicle. If the DIC still displays the SIDE BLIND ZONE SYS. UNAVAILABLE message after cleaning the bumper, see your dealer/retailer.

The SBZA displays may remain on if a trailer is attached to the vehicle, or a bicycle or object is extending out to either side of the vehicle.

When SBZA is disabled for any reason other than the driver turning it off, the driver will not be able to turn SBZA back on using the DIC. The SIDE BLIND ZONE ALERT ON option will not be selectable if the conditions for normal system operation are not met. Until normal operating conditions for SBZA are met, you should not rely upon SBZA while driving.

SBZA Error Messages

The following messages may appear in the DIC:

SIDE BLIND ZONE ALERT SYSTEM OFF: This message indicates that the driver has turned the system off.

SIDE BLIND ZONE SYS. UNAVAILABLE: This message indicates that the SBZA system is disabled because the sensor is blocked and cannot detect vehicles in the blind zone. The sensor may be blocked by mud, dirt, snow, ice, slush, or even heavy rainstorms. This message may also activate during heavy rain or due to road spray. The vehicle does not need service. For cleaning, see Washing Your Vehicle .

SERVICE SIDE BLIND ZONE ALERT SYSTEM: If this message appears, both SBZA displays will remain on indicating there is a problem with the SBZA system. If these displays remain on after continued driving, the system needs service. Take the vehicle to your dealer/retailer.