Code result
P0439
Catalyst Heater Control Circuit
Moderate severity
What it means
The drive circuit for the heated catalyst on bank 2 is open. Heated catalysts use an electrical heating element to reach light-off temperature within seconds of cold start.
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
Heater element or wiring open
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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