2013 PACCAR MX-13 – P0315 Cylinder unbalance – Detected

Fault code information

1 trip MIL
3 drive cycle recovery
Readiness group – Misfire
Freeze frame type – Fuel

Description of component(s)

Location of component(s)

Diagnostic condition

This diagnostic runs 30 seconds after the engine has started and when the engine is running at a steady speed and load between 600 and 1900 rpm.

Set condition of fault code

The PCI ECU (D420) detects an imbalance for more than 500 crankshaft revolutions.

Reset condition of fault code

This DTC changes to inactive when the fault is no longer detected. To validate the repair, drive the vehicle until the coolant temperature is at least 70°C [158°F]. Once the minimum target temperature has been reached, perform several low to higher speed accelerations with moderate engine load. Also perform high-load to low-load transitions. This activity should be conducted within the range of 15 km/h [10 mph] to 65 km/h [40 mph] for no more than 5 to 8 km [3 to 5 miles].

Electrical diagram(s)

Technical data

Possible causes

* Fuel injector failure
* Mechanical engine failure

Additional information

The detection of cylinder misfiring is based on piston acceleration, converted to crankshaft acceleration, which is directly related to the amount of torque that a cylinder produces. To determine crankshaft acceleration, several measurements are performed by the crankshaft sensor (F552) signal.

Leave a Reply

Your email address will not be published. Required fields are marked *