P2048Reductant Injection Valve Circuit Low (Bank 1 Unit 1)
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- Can trigger limp mode
- How the car detects it
- P2048 means the control line of the Bank 1, unit 1 DEF injector is pulled toward ground, typically a chafed wire touching the chassis or an internal short in the coil. GM's LML calibration treats less than about 0.5 ohm between signal and ground for 2 s as a failure (Type A). Ford's 2023 diesel logic reports the code once injector current exceeds 1.6 A; Deutz's EMR5 list files it under voltage below normal on the metering unit. Nissan reflashed the ECM of the 2016 to 2019 Titan XD with the Cummins 5.0 L V8 because P2048 appeared without a real defect, and Volvo traced it to a harness rubbed through on VNR trucks. While the code is active, dosing is normally blocked; the catalyst no longer reduces NOx and the inducement countdown may begin.
- What you may notice
- MIL on
- DEF dosing suspended, warning in the instrument cluster
- Inducement or reduced power after a countdown
- Likely causes
- LikelyControl wire chafed against chassis or exhaust bracket
- PossibleShorted winding inside the DEF injector
- PossibleECM software setting the code without a fault (Nissan Titan XD reflash)
- RareDEF residue or water bridging the connector pins
- 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 – €900
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.