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P2048 — Reductant Injector Circuit Low
SeriousDEF/SCRPower derate likely — plan to stop soon
Seen on: Heavy Truck/Diesel
Reductant Injector Circuit Low. Common causes: Doser circuit shorted to ground.
Don't risk it — get a diesel tech on the truck.
Your code rides along, so nearby mechanics see the fault before they quote you.
How serious is it?
Serious. Power derate likely — plan to stop soon.
Most likely causes
- Doser circuit shorted to ground
- Wiring damage
First moves (roadside)
- Check for chafed DEF doser harness near exhaust heat
FAQ
What does P2048 mean?
Reductant Injector Circuit Low. Common causes: Doser circuit shorted to ground.
How serious is P2048?
Serious — Power derate likely — plan to stop soon.
What's the most likely cause of P2048?
The most common cause is: Doser circuit shorted to ground. Other possibilities include Wiring damage.
Can I keep driving with P2048?
Power derate likely — plan to stop soon. When in doubt, get a qualified mobile diesel tech on the truck before continuing.
Throwing this code right now?
Find a mechanic or related guides
General diagnostic guidance for diesel engines (Cummins, Detroit, PACCAR, Volvo, Mack and more). Not a substitute for a scan-tool diagnosis on your specific truck.