Code result
P04F5
Catalyst Heater Circuit Low Bank 2
Moderate severity
What it means
The control or supply line to the electric catalyst heater on bank 2 is shorted to ground or measures below the expected voltage when the heater is commanded on.
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
Control line shorted to ground
highOne of the most commonly reported causes for this code — check this first.
Heater element internally shorted
mediumA plausible cause — test and verify before replacing parts.
Connector pins corroded - high contact resistance
lowLess common, but worth ruling out after the more likely causes.
Related help
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