Channel A ENGINE EEC Channel B Electrical connection (TYP) Programming plug Lanyard Shock mount (TYP) Test connection Figure 2-53.  EEC and programming plug.  differential transformer, and thermocouples. These sensors  feed engine parameter information from several systems back  to the EEC. The fuel control run cutoff switch controls the high pressure fuel shut off valve that allows or cuts off fuel  flow. The fuel temperature sensor thermocouple attaches to  the fuel outlet line on the rear of the fuel/oil cooler and sends  A and B and uses the cross-talk logic to find which EEC  channel is the best to control the output driver for a torque  motor or solenoid bank. The primary channel controls all of  the output drivers. If the cross-talk logic finds that the other  channel is better for control of a specific bank, the EEC  changes control of that one bank to the other channel. The  EEC has output driver banks that supply the control signals  to engine components. Each channel of the EEC supplies  the driver banks with control signals. The EEC has both  volatile and nonvolatile memory to store performance and  maintenance data. The EEC can control the engine thrust in two modes, which  can be selected by use of a mode selection switch. In the  normal mode, engine thrust is set with EPR; in the alternate  mode, thrust is set by N1. When the fuel control switch is  moved from run to cutoff, the EEC resets. During this reset,  all fault data is recorded in the nonvolatile memory. The EEC  controls the metering valve in the fuel metering unit to supply  fuel flow for combustion.  [Figure 2-54]  The fuel metering  unit is mounted on the front face of the gearbox and is  attached to the front of the fuel pump.  [Figure 2-55]  The EEC  also sends a signal to the minimum pressure and shutoff valve  in the fuel metering unit to start or stop fuel flow. The EEC  receives position feedback for several engine components  by using rotary differential transformer, linear variable  2-40 Figure 2-54.  Fuel metering unit.