GM-47976-503 is an adapter cable that allows injector and fuel system diagnosis with the GM-47976 AFIT on the 2.5L Colorado/Canyon truck. The Colorado/Canyon RPO code LCV 2.5L 4-cylinder engine uses an E80 ECM, whereas the Cadillac ATS 2.5L LCV uses the E39A ECM. The pinouts for the E80 are different from those of the E39A, so the GM-47976-502A Adapter Cable included in the previously essential GM-47976-500A SIDI Diagnostic Set will not test the 2.5L Colorado/Canyon. It will cause an error display on the AFIT. The GM-47976 AFIT is a previously essential tool for GM Tier 1, 2, 3, and 4 dealers in the USA and all dealers in Canada.
The AFIT was originally launched to dealers in 2006 to address two current issues at that time: improve the accuracy of diagnostics for the new AFIM (Air Fuel Imbalance Monitor) system due to increasing CARB requirements, and improve the accuracy of current service procedures to reduce misdiagnosis of current fuel systems to eliminate needless replacement of injectors that upon analysis by GM suppliers were found to be good.