P0615 — Starter Relay Circuit Fault
Seen on: Heavy Truck
Starter Relay Circuit Fault. Common causes: Starter relay circuit open or shorted.
Look up listed providers near you and give them this code when you call.
How serious is it?
Serious. Power derate likely — plan to stop soon.
Most likely causes
- Starter relay circuit open or shorted
- Failed relay
- wiring fault
First moves (roadside)
- Test starter relay coil and contacts
- check relay power supply
FAQ
Starter Relay Circuit Fault. Common causes: Starter relay circuit open or shorted.
Serious — Power derate likely — plan to stop soon.
The most common cause is: Starter relay circuit open or shorted. Other possibilities include Failed relay; wiring fault.
Power derate likely — plan to stop soon. When in doubt, get a qualified mobile diesel tech on the truck before continuing.
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.