Code result
P05F3
Exhaust Aftertreatment Power Relay Control Circuit Open
Moderate severity
What it means
The power relay that supplies the entire exhaust aftertreatment system (DOC, DPF, SCR sensors and heaters) reports an open control circuit. Aftertreatment effectively goes offline.
Is it safe to drive?
Use caution
The vehicle is usually drivable for short distances, but the problem can worsen or affect emissions. Diagnose and repair as soon as practical.
Most likely causes
Open in relay control or harness
highOne of the most commonly reported causes for this code — check this first.
Pin pushed back out of connector body
lowLess common, but worth ruling out after the more likely causes.
Cracked solder joint inside the module or sensor
lowLess common, but worth ruling out after the more likely causes.
Related help
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