The P0401 is insuffecient EGR flow,this is usually a stopped up EGR port in the intake manifold on this vehicle.
The other four codes are heater circuit codes for all four O2 heater circuits. This can be caused by just one bad O2 sensor. You can test these with an amp meter.Just unhook the PCM the hook and amp meter betwen first pin 93 and 103 then turn on the ignition switch and take a reading.You should have between 0.34 to 3.5 amps.Repeat this test at pins 94 and 103,95 and 103,and 96 and 103.
Fuse 23 is either for the blower relay if you are talking about the under hood fuse panel and for the 4X4 if in the under dash fuse panel.
Thanks Chuck... Right now the check engine light is off. Maybe I never reset the PCM after changing the DPFE. I'm holding my breath. I'm going to drive it today for a little while and see if I'm truly fixed. I will still accept your answer later today if it stays off since you went through the trouble. Otherwise, if the light comes back on, I willl follow your instructions and get back to you.
It turns out that my vacuum canister was leaking. The only problem now is finding one.