Code result
P23A6
Exhaust Heat Exchanger Bypass Valve B Stuck Open
Moderate severity
What it means
Bypass valve B is stuck in the open position - exhaust bypasses the heat exchanger continuously, slowing engine warm-up.
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
Valve stuck open
highOne of the most commonly reported causes for this code — check this first.
Carbon or debris buildup preventing free movement
lowLess common, but worth ruling out after the more likely causes.
Component wear with age - mechanical play
lowLess common, but worth ruling out after the more likely causes.
Related help
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