by Ben Klayman

Chrysler Group said on Thursday that it was recalling 33,443 light trucks in two separate campaigns to prevent false warnings from the tire pressure monitor systems.

Chrysler, a unit of Fiat Chrysler Automobiles, said it was unaware of any injuries or accidents related to the issue in either recall. All the affected vehicles are in the U.S. market.

Affected in one recall are an estimated 23,053 Ram ProMaster full-size commercial vans from model year 2014, the automaker said.

Chrysler said it would upgrade the software that helps the tire pressure monitor sensors recognize the tire from where the pressure data is coming. Absent that capability, a warning light may falsely signal tire pressure is low, raising the possibility the system may not properly alert drivers if tire pressure actually becomes too low.

The second recall affects an estimated 10,390 Jeep Wrangler SUVs and Dodge Grand Caravan/Chrysler Town & Country minivans from model year 2014, Chrysler said.

The company plans to reconfigure a tire pressure monitor module to disable a test mode that was inadvertently left on following shipment from the supplier. When installed, a module configured that way may not get an accurate tire-pressure reading, which could result in a false warning.

Chrysler said it would notify owners of the vehicles in both recalls next month and tell them when they may schedule service, which will be free.