I have a carrier weathermaker 8000 that won't light flashing error code 43 how do I fix it

Fault code 43: Low-heat pressure, draft safeguard, or auxiliary limit switch open while high-heat pressure switch closed. The draft safeguard and/or auxiliary limit switches can produce the situation you have if one or both opened, but most likely it is caused by a faulty low-heat pressure switch. Try this: Firmly wiggle the wires connected to the low-heat pressure switch (orange and yellow). Turn power off, then back on. Does the unit run now, without the fault code? If so, the LHPS contacts are failing. Replace the assembly.