Code result
P24B4
Particulate Matter Sensor Heater Control Circuit Range or Performance
Moderate severity
What it means
Same as P24B3 with the heater control loop in plausible range yet not matching the heater model. The sensor heater warms the element to operating temperature (~600 °C); without it the lambda sensor stays inactive in closed loop and the ECM cannot trim mixture.
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
highOne of the most commonly reported causes for this code — check this first.
Related help
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