Theory of Operation
WARNING: This page is about a different car, the 2011 RAM Cab & Chassis. However, it is still accessible from the selected car via links, so may be relevant.
The Powertrain Control Module (PCM) actuates the solenoid in the Fuel Injector causing the needle valve to rise and fuel flows through the spray holes in the nozzle tip into the combustion chamber. The PCM has a common internal driver circuit to all three Fuel Injectors on each bank. If any injector circuit on a given bank has a failure, a DTC will be set for all three Fuel Injectors on that bank. Fuel Injectors 1,2,3 are grouped together on bank 1. Fuel Injectors 4,5,6 are grouped together on bank 2. The MIL lamp will light immediately after the diagnostic runs and fails. During this time the customer may experience engine surge or stumble. The MIL lamp will turn off once the diagnostic runs and passes in four consecutive drive cycles.