Code result
P2AB1
Catalyst Heater Control Module Performance
Moderate severity
What it means
The ECM detects that the catalyst heater control module does not respond to commands within the expected window. Heating output is reduced or absent during catalyst light-off.
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
Internal control module fault
highOne of the most commonly reported causes for this code — check this first.
Communication with ECM degraded
mediumA plausible cause — test and verify before replacing parts.
Module software outdated, reflash may resolve
lowLess common, but worth ruling out after the more likely causes.
Related help
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