14652 - SPECIAL COVERAGE. ON SOME 2010-2012 MODEL YEAR CHEVROLET EXPRESS AND GMC SAVANA VEHICLES AND 2011-2012 MODEL YEAR CHEVROLET SILVERADO HD AND GMC SIERRA HD VEHICLES THAT ARE EQUIPPED WITH A 6.6L DIESEL ENGINE (LML/LGH), A MALFUNCTION-INDICATOR LIGHT (MIL) MAY ILLUMINATE DUE TO AN OFFSET IN THE TEMPERATURE SENSOR IN THE DIESEL-EMISSION-REDUCTION FLUID (DEF) TANK RESERVOIR, INCREASED TANK-HEATER RESISTANCE, OR REDUCTANT-SYSTEM PERFORMANCE. DEALERS ARE TO REPLACE THE DEF TANK RESERVOIR AND/OR SUPPLY MODULE PUMP.