Full — John Deere D1a Code

If the code persists, invest in a John Deere Service Advisor session. The hour of diagnostic time is cheaper than replacing a $2,000 DCU that wasn't broken.

Do not panic. Do not ignore it. Do not attempt an illegal delete.

| Repair Type | DIY Cost | Dealer Cost (Parts & Labor) | | :--- | :--- | :--- | | | $10 (tape/solder) | $250 – $450 | | Corroded connector replacement | $30 (new pigtail) | $350 – $600 | | DCU Module Replacement | $800 – $1,200 (part only) | $1,800 – $2,500 | | DEF Doser Valve Replacement | $500 – $700 | $1,200 – $1,800 | | Software Reflash | Not possible DIY | $200 – $400 |