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def issues

  1. E

    Deere 331g Def Issues

    Deere 331g Pin# 1T0331GKPHF311886. Engine is in derate after a def system issue warning and countdown. Only active codes i have are DCU 523636, DCU 3516. I drained tank and the fluid looks fine. I changed the dosing filter and the old filter looked fine. I am leaning towards the header unit but...
  2. C

    Cat 272D DEF Issue

    We were having an issue with our 272D2 skid steer related to the DEF system. I don't remember the exact fault but something like "DEF data valid not in range" We tore into the machine tried to clean out the system did replace the mass air flow sensor trying to figure out the issue with not much...
  3. G

    DEF Problems

    Good day all. I have a Cat 299D2 S/N DX202154 approx 2500 hrs that is experiencing DEF issues. It is throwing four codes relating to voltage to the 4 Reagent line heaters is below normal (ex 4354-4) It also codes 3361-5 Catalyst dosing unit current below normal. Cat has replaced the DCU...
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