Code 65, Injector Current Low: Notes

PCM has 2 injector driver circuits, each controlling a pair of injectors (1 and 4, or 2 and 3). PCM monitors current of each injector driver circuit by measuring voltage drop through a fixed resistor. PCM is able to control voltage drop. Current through each driver is allowed to rise to peak of 4 amps, enabling injectors to open quickly; current is then reduced to one amp, holding injectors open. This is called "peak and hold". If current cannot reach a 4-amp peak, Code 65 is set.