P0560 — System Voltage Malfunction
Seen on: Heavy Truck
System Voltage Malfunction. Common causes: Unstable system voltage.
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
- Unstable system voltage
- Weak battery
- charging system fault
- high resistance ground
First moves (roadside)
- Test battery load
- check alternator output voltage
- inspect main grounds
FAQ
System Voltage Malfunction. Common causes: Unstable system voltage.
Serious — Power derate likely — plan to stop soon.
The most common cause is: Unstable system voltage. Other possibilities include Weak battery; charging system fault; high resistance ground.
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.