VOLVO
ECM-P300411 - Power Sustain Relay. General Electrical Failures. Circuit short to ground
System
Engine Control Module (ECM)
Volvo models this fault code applies to
Applies to the following models:
1 modelV60 (2011–)
Show models by year and engine (2)
What does this fault code mean?
The code concerns the relay for the voltage supply, which the engine control module (ECM) monitors all the time. The relay feeds power to the high voltage battery's contactors, and without it the battery energy control module (BECM) receives no power. The code is set when the signal wire to the relay is shorted or has an open circuit.
Possible causes
- Mechanical fault on the relay
- Electrical fault on the relay
- Short circuit or open circuit in the wires to the relay
What you can do
- 1Read the code with a diagnostic tool and check whether it is active or only stored
- 2Check that the fuses are intact; their location is shown in the owner's manual
- 3Tell the workshop if anything has recently been done to the high voltage system or the engine control module
- 4Have a workshop check the relay and its wiring, since this belongs to the high voltage system and only trained personnel should handle it
Symptoms you may notice3
- The combustion engine runs in HYBRID mode more often than expected
- Temperature control or air conditioning does not work
- Warning symbol and text message in the display
General guidance for car owners. Diagnosis on the car can point to a different cause.