General Motors has announced four additional recalls, affecting such popular fleet vehicles as the 2014 model-year Chevrolet Silverado HD. This latest round of recalls covers a total of 89,126 vehicles.

GM said it informed the National Highway Traffic Safety Administration of the latest recall plans on June 5.

The largest of the four recalls includes 57,512 trucks and large SUVs that might have a defective base radio, preventing audible warnings when the key is left behind in the ignition or the front seat belt isn’t buckled. This recall affects the 2014 Chevrolet Silverado LD, 2014 GMC Sierra LD, 2015 Chevrolet Silverado HD, 2015 Chevrolet Tahoe, 2015 Chevrolet Suburban, 2015 GMC Sierra HD, 2015 GMC Yukon and 2015 GMC Yukon XL models.

Because of the radio defect, these vehicles may fall out of compliance with federal standards for protection against theft and collisions. Dealers will reprogram the radio control module, free of charge. GM said it is unaware of any crashes or injuries tied to this condition.

A second recall covers 31,520 2012 Buick Verano and Chevrolet Camaro, Cruze and Sonic compact cars that may have an air bag defect, GM said. The shorting bar inside the dual-stage driver's air bag might occasionally contact the air bag terminals. If such contact occurs, the air bag warning light will illuminate. This condition risks air bag deactivation during a crash. 

Dealers will replace the steering wheel air bag coil, which will eliminate any contact between the shorting bar and the air bag terminals, GM said. Repairs will be performed free of charge.

GM said it isaware of one crash with an injury where the relevant diagnostic trouble code was found during the vehicle's repair process.

"The company is aware of other crashes where air bags did not deploy but it is not known if they were related to this condition," GM said. The automaker conducted two previous recalls for this condition involving 7,116 vehicles.

A third recall covers 61 2013-2014 Chevrolet Spark and 2013 Buick Encore cars manufactured in Changwon, Korea, from Dec. 30, 2012, through May 8, 2013. These cars may have a condition in which the front passenger air bag end cap could separate from the air bag inflator. In a crash, this condition might prevent the passenger air bag from deploying properly. GM said it is unaware of any related crashes or injuries.

The fourth recall affects 33 2014 Chevrolet Corvettes in the U.S. because an internal short-circuit in the sensing and diagnostic module (SDM) could disable frontal air bags, safety belt pretensioners and the Automatic Occupancy Sensing module. GM dealers will replace the SDM on these vehicles. GM said it is unaware of any crashes or injuries related to the condition.