P2064Reductant/Regeneration Supply Control Circuit High
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- Can trigger limp mode
- How the car detects it
- P2064 closes the supply control group that begins with P2062. The line that switches power to the reductant supply, in a few layouts to regeneration hardware, carries a level that only a connection to a positive feed can explain, or the stage stays live while the controller has it switched off. No manufacturer documents P2064 publicly. Related component codes show how such a fault is caught: Deutz files a DEF pump high side shorted to battery as P05F0-00 on its EMR L1 secondary controller, and Ford's 2023 diesels set P208D once pump voltage tops 16 V or the pump controller draws over 5 A with the driver on, confirmed within 2 s. Suspects are a chafed wire touching a powered circuit, a welded relay contact or a wet connector. Unlike P2063 the pump may keep running unbidden, yet dosing is still suspended.
- What you may notice
- MIL and SCR or DEF warning in the cluster
- DEF pump audible after it should have stopped
- Countdown toward speed limit or no-restart after repeated faults
- Likely causes
- LikelyControl line chafed through and touching a powered wire
- PossibleSupply relay contact welded closed
- PossibleWater or corrosion bridging pins in the supply connector
- RareFaulty output stage in the controlling module
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- Repair
- Medium · Usually a job for a workshop.Typical cost: €80 – €600
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.