I am working on a 2006 F250, 115k miles. I have replaced injectors, glow plugs, glow plug module, filters. Still will not start. FICM has 48v koeo, and during cranking. Can the FICM be bad, even though the voltage is correct? A snapon scanner shows injector 1 circuit low. No other codes. Diagnosis on scanner lists FICM as possible issue. Anybody got any ideas. This thing is killing me.