Code result
P238A
Water in Fuel Sensor B Circuit
Moderate severity
What it means
A general circuit fault on the secondary water-in-fuel sensor B - typically used on diesel systems with two filter housings (pre-pump and post-pump). The ECU loses water-detection feedback on this stage; risk of water reaching the high-pressure pump and injectors.
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
Open in sensor or wiring
highOne of the most commonly reported causes for this code — check this first.
Related help
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