Code result
P04FE
Catalyst Heater Circuit Performance Bank 1
Moderate severity
What it means
The catalyst heater on bank 1 is electrically intact but does not deliver the expected thermal effect - measured catalyst light-off time is longer than calibrated. Heater element ageing, increased contact resistance, or a partial winding failure are typical causes.
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 aged - reduced power output
highOne of the most commonly reported causes for this code — check this first.
Increased contact resistance in supply
mediumA plausible cause — test and verify before replacing parts.
Related help
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